TW201900213A

TW201900213A - Modulation of immunoglobulin-A-positive cells

Info

Publication number: TW201900213A
Application number: TW107118022A
Authority: TW
Inventors: 曉伶廖; 強劉; 濤黃; 建輝周
Original assignee: 美商免疫醫療公司
Priority date: 2017-05-27
Filing date: 2018-05-25
Publication date: 2019-01-01
Also published as: WO2018222506A1

Abstract

Provided are compositions and methods for modulating, such as depleting, reducing, blocking the activation or immunosuppressive function of immunoglobulin-A (IgA)-producing cells. Also provided are methods for treating an IgA-associated condition, such as cancer, in a subject. In one embodiment, the method includes administering to the subject a therapeutically effective amount of an antibody or the antigen-binding fragment thereof specific to membrane-anchored IgA. Methods for preventing, detecting or diagnosing cancer in a subject with immunosuppressive microenvironment are also provided.

Description

Regulation of immunoglobulin A positive cells

本發明總體上涉及醫學、腫瘤學和免疫學領域。具體來講，本發明涉及對產生免疫球蛋白-A的細胞的調節及其在調節腫瘤微環境中的應用。The present invention relates generally to the fields of medicine, oncology, and immunology. In particular, the invention relates to the regulation of immunoglobulin-A producing cells and their use in modulating tumor microenvironments.

癌症仍然是世界範圍內巨大的公共健康挑戰，全世界每7例死亡中就有一例死於癌症。僅在美國就預計2016年約有60萬人死於某種形式的癌症，這是繼心臟病之後引起死亡的第二大常見原因。（2016年AACR癌症進展報告）。　　近年來，隨著對潛在生物學過程的瞭解的增加，癌症治療取得了重大進展。例如，誘導患者自身免疫系統對抗腫瘤的免疫療法的發展突出了提高對腫瘤抗原的免疫耐受的機制的重要性，所述腫瘤抗原為癌症相關遺傳改變所表達。這些免疫檢查點抑制劑（代表抑制劑為針對PD-1，PD-L1或CTLA4的單克隆抗體）已經在患有越來越多癌症類型的患者中產生了顯著且持久的應答。　　然而，目前的免疫療法（例如，PD-1或PD-L1阻斷）僅在癌症患者中呈現出有限的應答（參見，例如，Padmanee Sharma和James P. Allison, “Immune Checkpoint Targeting in Cancer Therapy:Toward Combination Strategies with Curative Potential” Cell (2015) 161:205-214），並且化療耐藥性仍然是癌症治療中最緊迫的主要困境之一。因此，仍舊需要開發調節免疫系統和消除免疫抑制性細胞的新方法，以解決腫瘤免疫耐受和化療耐藥。Cancer continues to be a huge public health challenge worldwide, with one in every seven deaths worldwide. In the United States alone, approximately 600,000 people are expected to die of some form of cancer in 2016, the second most common cause of death following heart disease. (2016 AACR Cancer Progress Report). In recent years, with the increase in understanding of potential biological processes, cancer treatment has made significant progress. For example, the development of immunotherapy that induces the patient's autoimmune system against tumors highlights the importance of mechanisms that increase immune tolerance to tumor antigens that are expressed by cancer-associated genetic alterations. These immunological checkpoint inhibitors (representing inhibitors are monoclonal antibodies against PD-1, PD-L1 or CTLA4) have produced significant and long-lasting responses in patients with more and more cancer types. However, current immunotherapies (eg, PD-1 or PD-L1 blockade) present only a limited response in cancer patients (see, for example, Padmanee Sharma and James P. Allison, "Immune Checkpoint Targeting in Cancer Therapy: Toward Combination Strategies with Curative Potential” Cell (2015) 161:205-214), and chemotherapy resistance remains one of the most pressing major dilemmas in cancer treatment. Therefore, there is still a need to develop new methods for modulating the immune system and eliminating immunosuppressive cells to address tumor immune tolerance and chemoresistance.

本發明涉及用於消除免疫抑制性B細胞的組合物和方法。在一方面，本發明涉及抗IgA抗體或其功能片段，以及其治療癌症的用途。在另一方面，本發明涉及在腫瘤微環境中消除IgA陽性漿細胞和減少免疫抑制或增加對癌症的免疫應答的組合物和方法。　　在一方面，本發明提供了特異性結合膜錨定形式的IgA（也稱為膜IgA或mIgA）的抗體或其抗原結合片段。在向所述受試者施用治療有效量的所述抗體或其片段時，所述抗體或其抗原結合片段消除或減少所述受試者中表達IgA細胞的數量。　　在一些實施方式中，所述抗體或其抗原結合片段可特異性結合IgA的細胞外膜近端結構域（EMPD）。在一些實施方式中，所述抗體或其抗原結合片段可特異性結合IgA的所述EMPD中的表位。在一些實施方式中，所述抗體或其抗原結合片段可特異性結合人IgA 1的所述EMPD中的表位。在一些實施方式中，所述抗體或其抗原結合片段可特異性結合人IgA 2的所述EMPD中的表位。在一些實施方式中，所述抗體或其抗原結合片段均可特異性結合IgA 1的所述EMPD和IgA 2的所述EMPD中的表位。在一些實施方式中，所述抗體或其抗原結合片段特異性結合包含SEQ ID NO：1或SEQ ID NO：2序列的肽。在一些實施方式中，所述抗體或其抗原結合片段可結合來源於人、恒河猴和食蟹猴的IgA。　　在一些實施方式中，所述抗體或其抗原結合片段可用于診斷癌症患者或腫瘤活檢中免疫抑制性B細胞的存在。　　在一些實施方式中，所述抗體可以是IgG。在一些實施方式中，所述抗體可以是IgG 1。在一些實施方式中，所述抗體或其片段具有ADCC活性。在一些實施方式中，所述抗體或其片段可誘導表達IgA細胞的凋亡。在一些實施方式中，所述抗體可以是具有糖基化修飾的IgG。在一些實施方式中，所述抗體可以是不具有岩藻糖基化的IgG（不具有岩藻糖基化的抗體也稱為非岩藻糖基化抗體），或具有降低的岩藻糖基化的IgG。　　在一些實施方式中，所述抗體消除或減少IgA陽性漿細胞（plasmocytes）。在一些實施方式中，所述抗體消除或減少IgA陽性漿細胞（plasma cells）。在一些實施方式中，所述抗體消除或減少IgA轉換的B細胞。在一些實施方式中，所述抗體消除或減少IgA漿母細胞。在一些實施方式中，所述抗體消除或減少IgA記憶B細胞。　　在一些實施方式中，所述抗體的抗原結合片段可選自ScFv（單鏈片段可變）抗體、Fab片段、F(ab’)₂ 片段和Fv片段。　　在一些實施方式中，所述抗體可以是嵌合抗體或雙特異性抗體。在一些實施方式中，所述抗體可以是人源化或全人抗體。　　在另一方面，本發明提供了一種抗體或其片段，當向所述受試者施用治療有效量的所述抗體或其片段時，所述抗體或其片段在所述受試者中特異性結合膜IgA並且阻斷表達IgA的B細胞的活性或免疫抑制性功能。　　在另一方面，本發明提供了一種包含本發明公開的所述抗體或其片段的組合物，以及至少一種藥學上可接受的載體。　　在另一方面，本發明提供了一種分離的編碼本發明提供的所述抗體或其片段的核酸。　　在另一方面，本發明提供了一種包含本發明提供的所述分離核酸的載體。　　在又一方面，本發明提供了一種包含本發明提供的所述載體的宿主細胞。在某些實施方式中，所述宿主細胞是哺乳動物細胞或CHO細胞。　　在另一方面，本發明提供了一種包含本發明提供的所述組合物的製造物品。在某些實施方式中，所述物品是藥瓶。在某些實施方式中，所述物品是預填充注射器。在某些實施方式中，所述物品進一步包含注射裝置。在某些實施方式中，所述注射裝置是自動注射器。　　在另一方面，本發明提供了一種製備特異性結合膜IgA的抗體或其功能片段的方法。所述方法包含在適於產生此類抗體或片段的條件下，以適於表達的形式培養含有編碼此類抗體或其片段的核酸的宿主細胞，以及回收所述抗體或片段。　　在另一方面，本發明提供了編碼或產生本發明提供的所述抗體或抗原結合片段的雜交瘤。　　在又一方面，本發明提供了治療患有癌症的受試者的方法，所述方法包含向所述受試者施用本發明提供的所述抗體或其抗原結合片段。　　在一些實施方式中，所述癌症可以是前列腺癌。　　在一些實施方式中，所述癌症可以是肝細胞癌（hepatocellular carcinoma）或肝細胞癌（hepatocellular cancer）（HCC）。　　在一些實施方式中，本發明所述抗體可與化學療法組合使用來治療癌症。　　在一些實施方式中，本發明所述抗體可與免疫原性化學療法組合使用來治療癌症。　　在一些實施方式中，本發明所述抗體可與靶向療法組合使用來治療癌症，所述靶向療法包括單克隆抗體和小分子藥物。　　在一些實施方式中，本發明所述抗體可與免疫療法組合使用來治療癌症。　　在一些實施方式中，本發明所述抗體可與免疫檢查點抑制劑組合使用來治療癌症。　　在一些實施方式中，本發明所述抗體可與一種或多種藥物組合使用，所述藥物選自鉑絡合物衍生物、奧沙利鉑、酪氨酸激酶抑制劑、PI3激酶抑制劑、BTK抑制劑、依魯替尼、抗PD-1的抗體、抗PD-L1的抗體、抗CTLA-4的抗體、抗LAG3的抗體、抗ICOS的抗體、抗TIGIT的抗體、抗TIM3的抗體、與腫瘤抗原結合的抗體、與T細胞表面標記物結合的抗體、與髓樣細胞或NK細胞表面標記物結合的抗體、烷化劑、亞硝基脲劑、抗代謝物、抗腫瘤抗生素、源自植物的生物鹼、拓撲異構酶抑制劑、激素治療藥、激素拮抗劑、芳香酶抑制劑和P-糖蛋白抑制劑。　　在一些實施方式中，本發明所述抗體可與包含CAR-T或TCR-T的細胞療法組合使用來治療癌症。　　在又一方面，本發明提供了一種用於在具有免疫抑制微環境的受試者中預防、檢測或診斷癌症的方法。在一些實施方式中，所述方法包括以下步驟：（i）從疑似患有或患有或具有患癌風險的受試者身上獲取樣品；（ii）將特異性結合膜IgA的抗體或其抗原結合片段與所述生物樣品接觸；（iii）確定所述生物樣品中IgA或表達IgA細胞的水準；以及（iv）將所述IgA或表達IgA的細胞水準與IgA或表達IgA細胞的參比水準進行比較。　　在一些實施方式中，所述樣品是血液樣品或腫瘤活檢。　　在一些實施方式中，所述受試者使用或已使用一種或多種藥物進行治療，所述藥物選自鉑絡合物衍生物、奧沙利鉑、酪氨酸激酶抑制劑、PI3激酶抑制劑、BTK抑制劑、依魯替尼、PD-1抗體、PD-L1抗體、CTLA-4抗體、LAG3抗體、ICOS抗體、TIGIT抗體、TIM3抗體、與腫瘤抗原結合的抗體、與T細胞表面標記物結合的抗體、與髓樣細胞或NK細胞表面標記物結合的抗體、烷化劑、亞硝基脲劑、抗代謝物、抗腫瘤抗生素、源自植物的生物鹼、拓撲異構酶抑制劑、激素治療藥、激素拮抗劑、芳香酶抑制劑和P-糖蛋白抑制劑。　　在一些實施方式中，所述方法還包括以下步驟：向所述受試者施用治療有效量的所述抗體或其抗原結合片段。The present invention relates to compositions and methods for eliminating immunosuppressive B cells. In one aspect, the invention relates to an anti-IgA antibody or a functional fragment thereof, and to the use thereof for the treatment of cancer. In another aspect, the invention relates to compositions and methods for eliminating IgA-positive plasma cells in a tumor microenvironment and reducing immunosuppression or increasing an immune response to cancer. In one aspect, the invention provides an antibody or antigen-binding fragment thereof that specifically binds to a membrane-anchored form of IgA (also known as membrane IgA or mIgA). When a therapeutically effective amount of the antibody or fragment thereof is administered to the subject, the antibody or antigen-binding fragment thereof eliminates or reduces the amount of IgA cells expressed in the subject. In some embodiments, the antibody or antigen-binding fragment thereof can specifically bind to the extracellular membrane proximal domain (EMPD) of IgA. In some embodiments, the antibody or antigen-binding fragment thereof can specifically bind to an epitope in the EMPD of IgA. In some embodiments, the antibody or antigen-binding fragment thereof can specifically bind to an epitope in the EMPD of human IgA1. In some embodiments, the antibody or antigen-binding fragment thereof can specifically bind to an epitope in the EMPD of human IgA2. In some embodiments, the antibody or antigen-binding fragment thereof can specifically bind to an epitope in the EMPD of the EMPD and IgA 2 of IgA 1 . In some embodiments, the antibody or antigen-binding fragment thereof specifically binds to a peptide comprising the sequence of SEQ ID NO: 1 or SEQ ID NO: 2. In some embodiments, the antibody or antigen-binding fragment thereof binds to IgA derived from humans, rhesus monkeys, and cynomolgus monkeys. In some embodiments, the antibody or antigen-binding fragment thereof can be used to diagnose the presence of immunosuppressive B cells in a cancer patient or tumor biopsy. In some embodiments, the antibody can be an IgG. In some embodiments, the antibody can be IgG1. In some embodiments, the antibody or fragment thereof has ADCC activity. In some embodiments, the antibody or fragment thereof can induce apoptosis in expressing IgA cells. In some embodiments, the antibody can be an IgG having a glycosylation modification. In some embodiments, the antibody may be an IgG that does not have fucosylation (an antibody that does not have fucosylation, also known as a non-fucosylated antibody), or has a reduced fucosyl group IgG. In some embodiments, the antibody eliminates or reduces IgA-positive plasmocytes. In some embodiments, the antibody eliminates or reduces IgA positive plasma cells. In some embodiments, the antibody eliminates or reduces IgA-converted B cells. In some embodiments, the antibody eliminates or reduces IgA plasmablasts. In some embodiments, the antibody eliminates or reduces IgA memory B cells. In some embodiments, the antigen-binding fragment of the antibody can be selected from the group consisting of a ScFv (single-chain fragment variable) antibody, a Fab fragment, an F(ab') ₂ fragment, and an Fv fragment. In some embodiments, the antibody can be a chimeric antibody or a bispecific antibody. In some embodiments, the antibody can be a humanized or fully human antibody. In another aspect, the invention provides an antibody or fragment thereof, wherein said antibody or fragment thereof is specific in said subject when said therapeutically effective amount of said antibody or fragment thereof is administered to said subject The membrane IgA is bound and blocks the activity or immunosuppressive function of IgA-expressing B cells. In another aspect, the invention provides a composition comprising the antibody or fragment thereof disclosed herein, and at least one pharmaceutically acceptable carrier. In another aspect, the invention provides an isolated nucleic acid encoding the antibody or fragment thereof provided by the invention. In another aspect, the invention provides a vector comprising the isolated nucleic acid provided by the invention. In yet another aspect, the invention provides a host cell comprising the vector provided by the invention. In certain embodiments, the host cell is a mammalian cell or a CHO cell. In another aspect, the invention provides an article of manufacture comprising the composition provided by the invention. In certain embodiments, the article is a vial. In certain embodiments, the item is a pre-filled syringe. In certain embodiments, the article further comprises an injection device. In certain embodiments, the injection device is an autoinjector. In another aspect, the invention provides a method of making an antibody or a functional fragment thereof that specifically binds to membrane IgA. The methods comprise culturing a host cell comprising a nucleic acid encoding such an antibody or fragment thereof, and recovering the antibody or fragment, in a form suitable for expression, under conditions suitable for the production of such antibody or fragment. In another aspect, the invention provides a hybridoma encoding or producing the antibody or antigen-binding fragment provided by the invention. In yet another aspect, the invention provides a method of treating a subject having cancer, the method comprising administering to the subject the antibody or antigen-binding fragment thereof provided by the invention. In some embodiments, the cancer can be prostate cancer. In some embodiments, the cancer can be hepatocellular carcinoma or hepatocellular cancer (HCC). In some embodiments, the antibodies of the invention can be used in combination with chemotherapy to treat cancer. In some embodiments, the antibodies of the invention can be used in combination with immunogenic chemotherapy to treat cancer. In some embodiments, the antibodies of the invention can be used in combination with targeted therapies to treat cancer, including monoclonal antibodies and small molecule drugs. In some embodiments, the antibodies of the invention can be used in combination with immunotherapy to treat cancer. In some embodiments, the antibodies of the invention can be used in combination with an immunological checkpoint inhibitor to treat cancer. In some embodiments, the antibodies of the invention may be used in combination with one or more drugs selected from the group consisting of platinum complex derivatives, oxaliplatin, tyrosine kinase inhibitors, PI3 kinase inhibitors, BTK Inhibitor, Ibrutinib, anti-PD-1 antibody, anti-PD-L1 antibody, anti-CTLA-4 antibody, anti-LAG3 antibody, anti-ICOS antibody, anti-TIGIT antibody, anti-TIM3 antibody, and a tumor antigen-bound antibody, an antibody that binds to a T cell surface marker, an antibody that binds to a myeloid cell or an NK cell surface marker, an alkylating agent, a nitrosourea agent, an antimetabolite, an antitumor antibiotic, and a Plant alkaloids, topoisomerase inhibitors, hormonal therapeutics, hormone antagonists, aromatase inhibitors, and P-glycoprotein inhibitors. In some embodiments, the antibodies of the invention can be used in combination with cell therapy comprising CAR-T or TCR-T to treat cancer. In yet another aspect, the invention provides a method for preventing, detecting or diagnosing cancer in a subject having an immunosuppressive microenvironment. In some embodiments, the method comprises the steps of: (i) obtaining a sample from a subject suspected of having or having or at risk of developing cancer; (ii) an antibody or antigen thereof that specifically binds to membrane IgA The binding fragment is contacted with the biological sample; (iii) determining the level of IgA or expressing IgA cells in the biological sample; and (iv) determining the level of the IgA or IgA-expressing cell with IgA or a level of expression expressing IgA cells Compare. In some embodiments, the sample is a blood sample or a tumor biopsy. In some embodiments, the subject is treated or has been treated with one or more drugs selected from the group consisting of platinum complex derivatives, oxaliplatin, tyrosine kinase inhibitors, PI3 kinase inhibitors , BTK inhibitor, Ibrutinib, PD-1 antibody, PD-L1 antibody, CTLA-4 antibody, LAG3 antibody, ICOS antibody, TIGIT antibody, TIM3 antibody, antibody binding to tumor antigen, and T cell surface marker Bound antibodies, antibodies that bind to myeloid cells or NK cell surface markers, alkylating agents, nitrosourea agents, antimetabolites, antitumor antibiotics, plant-derived alkaloids, topoisomerase inhibitors, Hormone therapeutics, hormone antagonists, aromatase inhibitors, and P-glycoprotein inhibitors. In some embodiments, the method further comprises the step of administering to the subject a therapeutically effective amount of the antibody or antigen-binding fragment thereof.

以下對本發明的描述僅旨在說明本發明的各種實施方式。因此，所討論的具體修改不應被解釋為對本發明範圍的限制。對於本領域技術人員顯而易見的是，在不脫離本發明的範圍的情況下可以進行各種等同、改變和修改，並且應當理解，這些等同的實施方式將包括在本發明中。本發明引用的所有參考文獻，包括出版物、專利和專利申請，均通過引用整體併入本發明。定義本發明使用的單數形式“一（a）”、“一個（an）”和“所述（the）”包括複數形式，除非上下文另外明確指出。　　當提及諸如量、持續時間等可測量值時，本發明所用的術語“約”意味著包含與指定值相差±10%的變化。除非另有說明，否則在本說明書和權利要求中使用的表示成分的量、性質（如分子量）、反應條件等的所有數字應理解為在所有情況下均由術語“約”修飾。相應地，除非表示相反，以下說明書和所附權利要求中所闡明的數字參數是近似值，其可根據本發明公開的主題所要實現的預期屬性而變化。最起碼，並不是企圖將等同原則的應用限制在權利要求的範圍內，各數值參數應當至少按照所報導的有效數字的數值並採用一般舍入技術來理解。儘管為本發明限定了較寬範圍的數字範圍和參數為近似值，但在具體實施例中所記錄的數值盡可能為精確值。但是，任何數值都包含某些必然由其各自測試量度中標準差所造成的固有誤差。　　本文使用的術語“抗原”（Ag）是指能夠誘導適應性免疫應答的物質。具體來說，抗原是一種可作為適應性免疫應答受體的靶標的物質。抗原通常是蛋白質和多糖，比較少見的是脂質。合適的抗原包括但不限於細菌的部分（外殼、莢膜、細胞壁、鞭毛、菌毛和毒素）、病毒和其他微生物。抗原還包括腫瘤抗原，例如，由腫瘤突變產生的抗原。如本文所用，抗原還包括免疫原和半抗原。　　如本文所用的術語“抗體”包括結合特定抗原（或多種抗原）的任何免疫球蛋白、單克隆抗體、多克隆抗體、多特異性抗體或雙特異性（二價）抗體。天然完整抗體包含兩條重鏈和兩條輕鏈。每條重鏈由可變區（V_H ）和第一、第二和第三恒定區（C_H 1，C_H 2，C_H 3）組成，而每條輕鏈由可變區（V_L ）和恒定區（C_L ）組成。哺乳動物重鏈分類為α、δ、ε、γ和μ，且哺乳動物輕鏈分類為λ或κ。抗體具有“Y”形狀，其中Y的莖由通過二硫鍵結合在一起的兩條重鏈的第二和第三恒定區組成。Y的每個臂包括單個重鏈中的可變區和第一恒定區，所述重鏈與單個輕鏈的可變區和恒定區結合。輕鏈和重鏈的可變區負責抗原結合，並且通常稱為Fv（對於可變片段）或Fv片段。兩種鏈中的可變區通常包含三個高度可變的環，稱為互補決定區（CDR）（輕（L）鏈CDR包括LCDR1、LCDR2和LCDR3，重（H）鏈CDR包括HCDR1、HCDR2、HCDR3）。本發明公開的抗體和抗原結合片段的CDR邊界可通過Chothia、Kabat或Al-Lazikani的慣例來定義或鑒定（Chothia, C等人，J Mol Biol 186(3):651-63 (1985)；Chothia, C.和Lesk, A.M., J Mol Biol, 196:901 (1987)；Chothia, C等人，Nature 342 (6252):877-83 (1989)；Kabat E.A.等人，National Institutes of Health, Bethesda, Md.(1991); Al-Lazikani, B.、Chothia, C.、Lesk, A. M.、J Mol Biol 273(4):927 (1997)）。三個CDR插入稱為框架區（FR）的側翼延伸區之間，框架區比CDR更加高度保守並形成支撐高變環的支架。重鏈和輕鏈的恒定區不參與抗原結合，但表現出各種效應功能。基於其重鏈恒定區的氨基酸序列將抗體分配成各種類別。抗體的五個主要類別或同種型是IgA、IgD、IgE、IgG和IgM，其特徵在於分別存在α、δ、ε、γ和μ重鏈。這幾種主要抗體類別可分為亞類，比如，人中的IgG1（γ1重鏈）、IgG2（γ2重鏈）、IgG3（γ3重鏈）、IgG4（γ4重鏈）、IgA1（α1重鏈）或IgA2（α2重鏈）和小鼠中的IgG1（γ1重鏈）、IgG2a（γ2a重鏈）、IgG2b（γ2b重鏈）和IgG3（γ3重鏈）。　　如本發明所用的術語“抗原結合片段”是指能夠與抗原特異性結合的蛋白質的一部分。在某些實施方式中，抗原結合片段衍生自包含一個或多個CDR的抗體，或結合抗原但不包含完整天然抗體結構的任何其他抗體片段。在某些實施方式中，抗原結合片段不是衍生自抗體，而是衍生自受體。抗原結合片段的實例包括，但不限於，雙抗體、Fab、Fab’、F(ab’)₂ 、Fv片段、二硫鍵穩定的Fv片段（dsFv）、(dsFv)₂ 、雙特異性dsFv（dsFv-dsFv’）、二硫鍵穩定的雙抗體（ds雙抗體）、單鏈抗體分子（scFv）、scFv二聚體（二價雙抗體）、多特異性抗體、單結構域抗體（sdAb）、駱駝抗體或納米抗體、結構域抗體和二價結構域抗體。在某些實施方式中，抗原結合片段能夠與親本抗體結合的相同抗原結合。在某些實施方式中，抗原結合片段可包含來自特定人抗體的一個或多個CDR，所述特定人抗體被移植到來自一種或多種不同人抗體的框架區。在某些實施方式中，抗原結合片段衍生自受體並含有一個或多個突變。在某些實施方式中，抗原結合片段不與受體的天然配體結合，該抗原結合片段衍生自所述受體。　　關於抗體的“Fab”是指由單個輕鏈（可變區和恒定區）組成的抗體部分，該部分通過二硫鍵與單個重鏈的可變區和第一恒定區結合。　　“Fab’”是指包含鉸鏈區一部分的Fab片段。　　“F(ab’)₂ ”是指Fab’的二聚體。　　關於抗體的“Fc”是指由第一重鏈的第二和第三恒定區組成的抗體部分，該部分通過二硫鍵與第二重鏈的第二和第三恒定區結合。抗體的Fc部分負責各種效應功能，例如ADCC和CDC，但在抗原結合中不起作用。關於本申請的“Fc”還指單個重鏈的第二和第三恒定區。野生型Fc是指通常在自然界中發現的沒有修飾或突變的Fc序列。　　由哺乳動物細胞產生的天然抗體的Fc區通常包含分支狀的雙觸角寡糖，該雙觸角寡糖通常通過N-連接鍵連接至Fc區的CH2結構域的Asn297。參見，例如，Wright等人，TIBTECH (1997) 15:26-32。所述寡糖可包含各種碳水化合物（例如，甘露糖、N-乙醯葡糖胺（GlcNAc）、半乳糖和唾液酸）以及與雙觸角寡糖結構的“莖”中的GlcNAc連接的岩藻糖。附著于Fc區的碳水化合物可以改變。在一些實施方式中，可對IgG中的寡糖進行修飾，以產生具有某些其他改善的性質的IgG。例如，提供了具有碳水化合物結構的抗體修飾，所述碳水化合物結構缺乏（直接或間接）附著于Fc區的岩藻糖。這種稱為“非岩藻糖基化”的修飾可具有改善的ADCC功能。參見，例如，美國專利公開號 US 2003/0157108（Presta, L.）；US 2004/0093621（Kyowa Hakko Kogyo Co., Ltd）。與“非岩藻糖基化”、“去岩藻糖基化”或“岩藻糖缺乏”抗體修飾相關的出版物的實例包括：US 2003/0157108；WO 2000/61739；WO 2001/29246；US 2003/0115614；US 2002/0164328；US 2004/0093621；US 2004/0132140；US 2004/0110704；US 2004/0110282；US 2004/0109865；WO 2003/085119；WO 2003/084570；WO 2005/035586；WO 2005/035778；WO2005/053742；WO2002/031140；Okazaki等人J. MoL Biol.336：1239-1249 (2004)；Yamane-Ohnuki等人Biotech.Bioeng.87：614 (2004)。能夠產生去岩藻糖基化抗體的細胞系的實例包括缺乏蛋白質岩藻糖基化的Lee 13CHO細胞（Ripka等人Arch.Biochem.Biophys.(1986) 249:533-545；美國專利申請公開號 2003/0157108 A1，Presta, L；以及WO 2004/056312 A1，Adams等人，特別是實施例11），敲除細胞系，比如，α-1,6-岩藻糖基轉移酶基因、FUT8、敲除CHO細胞（參見，例如，Yamane-Ohnuki等人，Biotech, Bioeng. (2004) 87:614；Kanda, Y.等人，Biotechnol. Bioeng., (2006) 94(4):680-688；以及WO2003/085107)。　　關於抗體的“Fv”是指攜帶完整抗原結合位點的抗體的最小片段。通常，Fv片段由單個輕鏈（V_L ）的可變區組成，所述單個輕鏈（V_L ）的可變區與單個重鏈（V_H ）的可變區結合。關於本申請的“Fv”還指單個輕鏈或單個重鏈的可變區。在某些實施方式中，本發明所述的Fv片段是突變的並不具有完整的抗原結合位點。　　如本發明所用的“抗體依賴性細胞介導的細胞毒性”或ADCC是指一種細胞毒性形式，其中與存在於某些細胞毒性細胞（例如，自然殺傷（NK）細胞、中性粒細胞和巨噬細胞）上的Fc受體（FcR）結合的分泌的Ig，使得這些細胞毒性效應細胞能夠特異性結合於攜帶抗原的靶細胞，並隨後使用細胞毒素殺死靶細胞。抗體“武裝”細胞毒性細胞，並通過該機制殺死靶細胞。作為介導ADCC的主要細胞的NK細胞僅表達FcγRIII，而單核細胞表達FcγRI、FcγRII和FcγRIII。Ravetch和Kinet,Annu. Rev. Immunol. (1991)9: 457-92中第464頁表3總結了造血細胞上的Fc表達。為了評估目標分子的ADCC活性，進行體外ADCC測定，比如，如美國專利號5,500,362或5,821,337中所述的體外ADCC測定。用於此類測定的有用效應細胞包括外周血單核細胞（PBMC）和自然殺傷（NK）細胞。可選地或另外地，可在體內評估目標分子的ADCC活性，例如，在動物模型中，比如，Clynes等人，PNAS USA (1998) 95: 652-656中公開的動物模型。　　如本發明所用的“補體依賴性細胞毒性”或“CDC”是指在補體存在下裂解靶細胞。經典補體途徑的啟動是通過補體系統的第一組分（C1q）與同其同源抗原結合的抗體（合適的亞類）的結合而啟動。為了評估補體啟動，可進行CDC測定，例如，如Gazzano-Santoro等人，J. Immunol. Methods (1996)202: 163中所述。　　如本發明所用的“載體”包括藥學上可接受的對暴露於所用劑量和濃度的細胞或哺乳動物無毒的載體、賦形劑或穩定劑。藥學上可接受的載體通常是含水pH緩衝溶液。藥學上可接受的載體的實例包括緩衝劑，比如，磷酸鹽、檸檬酸鹽和其他有機酸；包含抗壞血酸的抗氧化劑；低分子量（少於約10個殘基）多肽；蛋白質，比如，血清白蛋白、明膠或免疫球蛋白；親水性聚合物，比如，聚乙烯吡咯烷酮；氨基酸，比如，甘氨酸、穀氨醯胺、天冬醯胺、精氨酸或賴氨酸；單糖、二糖和其他碳水化合物，包括葡萄糖、甘露糖或糊精；螯合劑，比如，EDTA；糖醇，比如，甘露醇或山梨醇；成鹽反離子，比如，鈉；和/或非離子表面活性劑，比如，TWEEN™、聚乙二醇（PEG）和PLURONICS™。　　“特異性結合”或“特異於”特定多肽或特定多肽上的表位的抗體是結合特定多肽或特定多肽上的表位而基本上不結合任何其他多肽或多肽表位的抗體。例如，本發明的IgA特異性抗體的EMPD特異於B細胞上膜結合的IgA上發現的IgA的EMPD，但後者在分泌的IgA上不存在。在一些實施方式中，與IgA的EMPD結合的抗體的解離常數（Kd）為≦100 nM、≦10 nM、≦1 nM、≦0.1 nM、≦0.01 nM或≦0.001 nM（例如，10^-8 M或更低，例如，從10^-8 M到10^-13 M，例如，從10^-9 M到10^-13 M）。　　“誘導細胞凋亡”或“凋亡”的抗體是通過標準凋亡測定法（比如，膜聯蛋白V結合、DNA片段化、細胞收縮、內質網擴張、細胞碎裂、和/或膜囊泡的形成（稱為凋亡小體））確定的誘導程式性細胞死亡的那些抗體，。例如，本發明的抗IgA抗體的細胞凋亡活性可通過用膜聯蛋白V染色表面結合IgA的細胞來顯示。 “單鏈Fv抗體”或“scFv”是指由輕鏈可變區和重鏈可變區組成的工程化抗體，所述輕鏈可變區和重鏈可變區直接或通過肽接頭序列彼此連接（Huston Js等人，Proc Natl Acad Sci USA, 85:5879(1988)）。“單鏈Fv-Fc抗體”或“scFv-Fc”是指由與抗體的Fc區連接的scFv組成的工程化抗體。　　“單域抗體”、“sdAb”、“駱駝抗體”、“重鏈抗體”或“HCAb”是指含有兩個V_H 結構域且沒有輕鏈的抗體（Riechmann L.和Muyldermans S., J, Immunol Methods 231(1-2):25-38 (1999)；Muyldermans S., J Biotechnol 74(4):277-302 (2001)；WO94/04678；WO94/25591；美國專利號6,005,079）。重鏈抗體最初來源於駱駝科（駱駝、單峰駱駝和美洲駝）。雖然沒有輕鏈，但駱駝抗體具有真正的抗原結合庫（Hamers-Casterman C.等人，Nature 363 (6428):446-8 (1993)；Nguyen VK.等人，Immunogenetics 54(1):39-47 (2002)；Nguyen VK.等人，Immunology 109(1):93-101 (2003)）。重鏈抗體的可變結構域（V_H H結構域）代表由適應性免疫應答產生的最小已知抗原結合單位（Koch-Nolte F.等人，FASEB J 21(13): 3490-8.(2007)）。　　“納米抗體”是指由來自重鏈抗體或駱駝抗體的V_H H結構域和兩個恒定結構域C_H 2和C_H 3組成的抗體片段。　　“雙抗體”包括具有兩個抗原結合位點的小抗體片段，其中所述片段包含與同一多肽鏈中的V_L 結構域連接的V_H 結構域（V_H -V_L 或V_L -V_H ）（參加，例如，Holliger P.等人，Proc Natl Acad Sci U S A. 90(14):6444-8 (1993)；EP404097；WO93/11161）。通過使用太短而不允許同一鏈上的兩個結構域之間配對的接頭，迫使結構域與另一個鏈的互補結構域配對，從而產生兩個抗原結合位點。抗原結合位點可靶向相同或不同抗原（或表位）。　　“結構域抗體”是指僅含有重鏈可變區或輕鏈可變區的抗體片段。在某些實施方式中，兩個或更多個V_H 結構域與肽接頭共價連接以產生二價或多價結構域抗體。二價結構域抗體的兩個V_H 結構域可靶向相同或不同的抗原。　　在某些實施方式中，“(dsFv)₂ ”包含三條肽鏈：通過肽接頭連接並通過二硫鍵與兩個V_L 部分結合的兩個V_H 部分。　　在某些實施方式中，“雙特異性ds雙抗體”包含通過V_H1 和V_L1 之間的二硫鍵與V_L1 -V_H2 （也通過肽接頭連接）結合的V_H1 -V_L2 （通過肽接頭連接）。　　在某些實施方式中，“雙特異性dsFv”或“dsFv-dsFv”包含三條肽鏈：V_H1 -V_H2 部分，其中重鏈通過肽接頭（例如，長柔性接頭）連接，並分別通過二硫鍵與V_L1 和V_L2 部分結合，其中每個二硫鍵配對的重鏈和輕鏈具有不同的抗原特異性。　　在某些實施方式中，“scFv二聚體”是包含與另一V_H -V_L 部分二聚化的V_H -V_L （通過肽接頭連接）的二價雙抗體或二價ScFv（BsFv），從而一個部分的V_H 與另一個部分的V_L 配位元並形成兩個結合位點，所述兩個結合位點可靶向相同的抗原（或表位）或不同的抗原（或表位）。在其他實施方式中，“scFv二聚體”是包含與V_L1 -V_H2 （也通過肽接頭連接）連接的V_H1 -V_L2 （通過肽接頭連接）的雙特異性雙抗體，從而V_H1 和V_L1 配位，V_H2 和V_L2 配位，且每個配位對都具有不同的抗原特異性。　　本文所用的參考抗體或抗原結合片段的術語“人源化”意指抗體或抗原結合片段包含衍生自非人動物的CDR、衍生自人的FR區，和當可適用時，源自人的恒定區。在某些實施方式中，人源化抗體或抗原結合片段可用作人治療劑，因為它在人體中具有降低的免疫原性。在一些實施方式中，非人動物是哺乳動物，例如小鼠、大鼠、兔子、山羊、綿羊、豚鼠、倉鼠或駱駝。在一些實施方式中，除了非人CDR序列外，人源化抗體或抗原結合片段基本上由全人序列組成。在一些實施方式中，衍生自人的FR區可包含與其衍生自人的抗體相同的氨基酸序列，或者可包含一些氨基酸變化，例如，不超過10、9、8、7、6、5、4、3、2或1個氨基酸的變化。在一些實施方式中，氨基酸的這種變化可僅存在於重鏈FR區、僅存在於輕鏈FR區或存在於兩條鏈中。在一些優選的實施方式中，人源化抗體包含人FR1-3和人JH和Jκ。　　如本發明所用的術語“表位”是指抗體結合的抗原上特定原子或氨基酸基團。表位元可以是線性表位元或構象表位。線性表位元由來自抗原的連續氨基酸序列形成，並基於其一級結構與抗體相互作用。另一方面，構象表位由抗原氨基酸序列的不連續部分組成，並基於抗原的3D結構與抗體相互作用。通常，表位的長度約為五或六個氨基酸。如果兩種抗體呈現抗原的競爭性結合，則它們可以結合抗原內的相同表位。　　術語“治療性抗體（therapeutic antibody）”或“治療性抗體（therapeutic antibodies）”是指在市場授權之前或之後用作治療用途的抗體。　　如本發明所用的術語“納米顆粒”是指尺寸在1和1000納米之間的顆粒。在某些實施方式中，納米顆粒是尺寸在1到100納米之間的顆粒。已公開了很多納米顆粒，包括，例如，超順磁性氧化鐵（SPIO）納米顆粒（參見美國專利申請US20100008862）、金屬納米顆粒（例如，金或銀納米顆粒（參見，例如，Hiroki Hiramatsu, F.E.O., Chemistry of Materials 16, 2509-2511 (2004)））、半導體納米顆粒（例如，具有單個或多個組分的量子點，比如，CdSe/ZnS（參見，例如，M. Bruchez等人，science 281, 2013-2016 (1998)）、摻雜重金屬的量子點（參見，例如，Narayan Pradhan等人，J. Am. chem. Soc.129, 3339-3347 (2007)）或其他半導體量子點；聚合物納米顆粒（例如，由PLGA（聚（乳酸-共-羥基乙酸）（參見，例如，Minsoung Rhee等人，Adv. Mater. 23, H79-H83 (2011)）、PCL（聚己內酯）（參見，例如，Marianne Labet等人，Chem. Soc. Rev. 38, 3484-3504 (2009)）、PEG（聚乙二醇）或其他聚合物中的一種或其組合製成的顆粒）；矽質納米顆粒；以及非SPIO磁性納米顆粒（例如，MnFe2O4（參見，例如，Jae-Hyun Lee等人，Nature Medicine 13V95-99 (2006)）、合成反鐵磁納米顆粒（SAF）（參見，例如，A. Fu等人，Angew. Chem.Int. Ed.48, 1620-1624 (2009)），以及其他類型磁性納米顆粒。　　如本發明所用的“細胞”可以是原核的或真核的。例如，原核細胞包括細菌。例如，真核細胞包括真菌、植物細胞和動物細胞。動物細胞（例如，哺乳動物細胞或人類細胞）的類型包括，例如，來自迴圈/免疫系統或器官的細胞，例如，B細胞、T細胞（細胞毒性T細胞、自然殺傷T細胞、調節性T細胞、T輔助細胞）、自然殺傷細胞、粒細胞（例如，嗜鹼性粒細胞、嗜酸性粒細胞、中性粒細胞和過度分泌的中性粒細胞）、單核細胞或巨噬細胞、紅細胞（例如，網織紅細胞）、肥大細胞、血小板或巨核細胞和樹突細胞；來自內分泌系統或器官的細胞，例如，甲狀腺細胞（例如，甲狀腺上皮細胞、濾泡旁細胞）、甲狀旁腺細胞（例如，甲狀旁腺主細胞、嗜酸細胞）、腎上腺細胞（例如，嗜鉻細胞）和松果體細胞（例如，松果體細胞）；來自神經系統或器官的細胞，例如，膠質母細胞（例如，星形膠質細胞和少突膠質細胞）、小膠質細胞、大細胞神經分泌細胞、星狀細胞、蔔歇細胞和垂體細胞（例如，促性腺激素、皮質激素、甲狀腺素、生長激素和乳營養細胞）；來自呼吸系統或器官的細胞，例如，肺細胞（I型肺細胞和II型肺細胞）、克拉拉細胞、杯狀細胞和肺泡巨噬細胞；來自循環系統或器官的細胞（例如，心肌細胞和周細胞）；來自消化系統或器官的細胞，例如，胃主細胞、壁細胞、杯狀細胞、細胞細胞、G細胞、D細胞、ECL細胞、I細胞、K細胞、S細胞、腸內分泌細胞、腸嗜鉻細胞、APUD細胞和肝細胞（例如，肝細胞和庫普弗細胞）；來自外皮系統或器官的細胞，例如，骨細胞（例如，成骨細胞、骨細胞和破骨細胞）、牙齒細胞（例如，成牙骨質細胞和成釉細胞）、軟骨細胞（例如，軟骨細胞）、皮膚/毛細胞（例如，毛細胞、角質形成細胞和黑素細胞（痣細胞）、肌細胞（例如，肌細胞）、脂肪細胞、成纖維細胞和肌腱細胞；來自泌尿系統或器官的細胞（例如，足細胞、腎小球旁細胞、腎小球內腎小球膜細胞、腎小球外腎小球膜細胞、腎近端小管刷狀緣細胞和黃斑密度細胞）；以及來自生殖系統或器官的細胞（例如，精子、支援細胞、間質細胞、卵子、卵母細胞）。細胞可以是正常的、健康的細胞；或患病或不健康的細胞（例如，癌細胞）。細胞還包括哺乳動物受精卵或幹細胞，其包括胚胎幹細胞、胎兒幹細胞、誘導的多能幹細胞和成體幹細胞。幹細胞是能夠經歷細胞分裂迴圈同時保持未分化狀態並分化成特化細胞類型的細胞。幹細胞可以是全能幹細胞、多能幹細胞、寡能幹細胞和單能幹細胞，其中任何一種都可從體細胞誘導。幹細胞還可包括癌症幹細胞。哺乳動物細胞可以是齧齒動物細胞，例如小鼠、大鼠、倉鼠細胞。哺乳動物細胞可以是兔形目細胞，例如，兔細胞。哺乳動物細胞還可以是靈長類動物細胞，例如，人細胞。　　如本發明所用的“IgA相關疾病”是指由IgA或IgA表達細胞的表達或活性的增加或減少引起、加劇或以其他方式與其相關的任何疾病。這些可包括IgA腎病（IgAN）、Henoch-Schonlein紫癜（HSP）、乳糜瀉和癌症。　　術語“藥學上可接受的”表示指定的載體、媒介物、稀釋劑、賦形劑和/或鹽通常與包含製劑的其他成分在化學上和/或物理上相容，並在生理上與其受體相容。　　如本發明所用的術語“受試者”是指人或任何非人動物（例如，小鼠、大鼠、兔、狗、貓、牛、豬、綿羊、馬或靈長類動物）。人類包括產前和產後形式。在很多實施方式中，受試者是人類。受試者可以是患者，指呈現給醫療提供者以診斷或治療疾病的人。如本發明使用的術語“受試者”可與“個體”或“患者”互換。受試者可能患有或易患疾病或病症，但可能會或可能不會表現出疾病或病症的症狀。　　本發明所用的術語“治療有效量”或“有效劑量”是指有效治療與IgA或IgA表達細胞相關的疾病或病症的藥物的劑量或濃度。例如，關於本發明公開的抗體或抗原結合片段用於治療癌症的用途，治療有效量是能夠實現以下功能的抗體或抗原結合片段的劑量或濃度：減少腫瘤體積、根除全部或部分腫瘤、抑制或減緩腫瘤生長或癌細胞浸潤到其他器官、抑制介導癌症狀態的細胞的生長或增殖、抑制或減緩腫瘤細胞的轉移、改善與腫瘤或癌症相關的任何症狀或標誌物、預防或延遲腫瘤或癌症的發展，或其某些組合。　　本發明所用的“治療（treating、treatment）”病症包括預防或緩解病症、減緩病症的發作或發展速度、降低病症發生的風險、預防或延緩與病症相關症狀的發展、減少或結束與病症相關的症狀、產生病症的完全或部分消退、治癒病症或其某些組合。IgA 和產生 IgA 的細胞 取決於B細胞的分化階段，免疫球蛋白（Igs）表達為分泌蛋白或膜結合蛋白，。在B淋巴細胞的表面上，膜結合Igs構成B細胞受體（BCR）的抗原特異性組分。相反，當由分化的漿細胞產生時，Igs主動得到分泌，成為血清的相關組分。　　免疫球蛋白屬於免疫球蛋白超家族（IgSF）。它們由兩條重鏈（H）和兩條輕鏈（L）組成，其中L鏈可由κ 鏈或λ 鏈組成。每條組分鏈含有一個NH 2-末端“可變”（V）IgSF結構域和一個或多個COOH-末端“恒定”（C）IgSF結構域。每個V或C結構域由大約110-130個氨基酸組成，平均為12,000-13,000Da。　　兩條Ig L鏈僅含有一個C結構域，而Ig H鏈含有三個或四個這樣的結構域。具有三個C結構域的H鏈傾向於在第一（CH 1）和第二（CH 2）結構域之間包括間隔鉸鏈區。在所有同種型中，CH1都與輕鏈的C區相關。IgG和IgA的CH2和CH3結構域以及IgM和IgE的CH2、CH3和CH4結構域一起構成所謂的Fc片段，其對於膜形式和分泌形式都是共同的。　　然而，膜Igs含有三個額外的C末端結構域，即細胞外膜近端結構域（EMPD）、跨膜結構域（TMD）和細胞質結構域（CytoD）。這三個C末端結構域統稱為膜錨定肽區段。膜Igs也稱為膜結合Igs、膜錨定Igs、膜表達Igs或細胞表面Igs。　　Ig重鏈和輕鏈各自由單獨的多基因家族編碼，且V和C結構域各自單獨由獨立元件編碼：V（D）J基因區段編碼V結構域，而個體外顯子編碼C結構域。V結構域的一級序列在功能上被分成三個高變區間，稱為互補決定區（CDR），該區域位於稱為框架（FR）的四個穩定序列區域之間。位於VDJ基因座下游的是功能性CH基因。這些恒定基因由一系列外顯子組成，每個外顯子都編碼單獨的結構域、鉸鏈或末端。所有CH基因都可進行選擇性剪接以產生兩種不同類型的羧基末端：在B淋巴細胞表面上錨定免疫球蛋白的膜末端或在可溶形式的免疫球蛋白中出現的分泌末端。　　在B細胞發育早期，有效重排的可變結構域（VH和VL）與μ重鏈連合表達以產生IgM，然後通過選擇性剪接來產生IgD。在發育後期，這些可變結構域可回應於抗原刺激和細胞因數調節而在受控過程中與其他同種型（IgG、IgA和IgE）連合。每種同種型的CH基因在人14號染色體上以相同的轉錄方向進行排列。通過Cμ開關（S）區域與其他H鏈恒定區中的一個開關區域之間的重組（稱為類別切換或類別切換重組[CSR]的過程），相同的VDJ重鏈可變結構域可與任何H鏈類並置來產生各種Ig同種型。這使得B細胞能夠定制抗體分子的受體和效應末端以滿足特定需要。　　同種型在許多性質上不同，這包括大小、補體結合、FcR結合和對抗原的同種型回應。對同種型的選擇取決於抗原本身和被啟動的信號傳導途徑以及局部微環境而定。　　作為大多數哺乳動物粘膜分泌物中存在的主要抗體類別，IgA代表著防止從易感的粘膜表面吸入和攝入的病原體入侵的關鍵第一道防線。粘膜分泌物中的分泌型IgA（S-IgA）可結合抗原（Ags），從而限制它們的吸收，抑制細菌附著到粘膜表面，並中和可能以其他方式通過粘膜表面進入身體的各種病毒。由於IgA無法有效地啟動補體，所以不會發生潛在的宿主破壞性炎症反應。　　在許多物種的血清中也發現濃度顯著的IgA，其中其起第二道防線的作用，即介導對已破壞粘膜表面的病原體的消除。血清中的IgA能夠結合並中和Ags（比如，存在於微生物上的Ags），並可幫助中和自身抗原或清除進入體內的少量食物Ags。對自身抗原或外源性Ags的中和可防止對這些Ags產生的不適當的免疫應答。在IgA缺乏的受試者中自身免疫疾病的發病率增加，這一發現支持了後一假說。　　雖然在血清中的IgA通常是單體，粘膜中的IgA（稱為分泌型IgA（S-IgA））是與J鏈和另一種多肽鏈（分泌組分）相關的二聚體（有時是三聚體和四聚體）。與IgM類似，IgA的CH3結構域具有短鏈尾，J鏈通過二硫鍵與該短鏈結合，而分泌組分通過二硫鍵與二聚體的CH2結構域之一結合。這種聚合形式的IgA與聚合免疫球蛋白受體（pIgR）特異性結合，並通過上皮細胞的細胞質轉運至腸道內腔或其他粘膜表面。IgM也與pIgR結合，並可通過相同的機制分泌到腸道中。　　IgA在數量上是體內產生的主要Ig同種型。據估計，所有產生Ig的細胞中有70-80%位於腸粘膜中。因此，IgA是迄今為止個體中最豐富的免疫球蛋白，其大部分存在於粘膜分泌物中。血清IgA水準一般高於IgM，但遠低於IgG。相反，粘膜表面和分泌物中（包括唾液和母乳）的IgA水準遠高於IgG。特別地，IgA可在初乳中貢獻高達50%的蛋白質，這是母親給予新生兒的“第一種牛奶”。　　遺傳序列分析和功能比較已表明：免疫球蛋白A（IgA）存在於所有哺乳動物（胎盤、有袋動物和單孔目動物）和鳥類中。人類、黑猩猩、大猩猩和長臂猿有兩個IgA重鏈恒定區（Cα）基因，該基因產生兩個亞類，即IgA1和IgA2，而檢查的大多數其他物種（紅猩猩、恒河猴和食蟹猴、牛、馬、豬、狗、小鼠、大鼠、針鼴和負鼠）只有一個類似於Cα2的Cα基因。只擁有單個類似IgA1的IgA的紅猩猩可能已經失去了它們的IgA2。對於兔子（兔類動物），在此則是一個有趣的例外，它具有13個Cα基因，其中12個似乎得到表達。單個IgA基因也可被認為存在於大多數鳥類中，因為它們已經在被認為是現存最原始的鳥類之一的雞和鴨中得到描述。　　人體內有兩種IgA亞類，即IgA1和IgA2，二者的結構差異主要在於它們的鉸鏈區。IgA1分子具有較長的鉸鏈區，該鉸鏈區是位於抗體核心處的柔性拉伸多肽，起分割負責抗原結合區和效應能力區的作用。與IgA1相比，IgA2缺失了鉸鏈區中的13個氨基酸序列。與IgA1相比，較短的鉸鏈區更好地保護了IgA2不受細菌蛋白酶的作用。這種針對蛋白酶消化的增強保護作用可解釋為什麼IgA2在許多粘膜分泌物中佔優勢（腸道中IgA2與IgA1的比例為3：2），而超過90%的血清IgA是IgA1形式。　　已在一些物種中研究出了IgA的等位變異，但在許多其他物種中仍有待研究。在人中，IgA2亞類有兩個（或可能三個）等位基因。IgA2的兩種同種異型（遺傳）變體在重鏈和輕鏈之間的連接點不同。恒河獼猴IgA也顯示出了等位元基因多態性，而限制性片段長度多態性（RFLP）證據則表明存在牛IgA和馬IgA的同種異型。小鼠IgA以不同的等位基因形式存在，其特徵在於其鉸鏈區。類似的，豬IgA的兩個等位基因變體在鉸鏈區中不同。　　人IgA1和IgA2都具有膜結合形式（mIgA1和mIgA2），其中含有相應的mα1和mα2重鏈，該二條重鏈與α1和α2不同之處在於從α1和α2的CH3結構域延伸的三個額外的C-末端結構域，即細胞外膜近端結構域（EMPD）、跨膜結構域（TMD）和細胞質結構域（CytoD）。這三個C末端結構域統稱為膜錨定肽區段。在其他Ig同種型（包括IgM、IgD、IgG和IgE）中也已鑒定出了類似的膜錨定肽區段。在大多數Ig同種型（膜IgA除外）中，這三個結構域由另外兩個稱為M1和M2的外顯子來進行編碼。外顯子M1編碼EMPD和TMD，而M2則編碼CytoD。在膜IgA的情況下，單一個外顯子編碼EMPD、TMD和CytoD。　　重鏈mα1以短和長同種型而存在，稱為mα1S和mα1L，後者在細胞外區段（EMPD結構域）的N-末端含有額外的6個氨基酸殘基GSCSVA。經調查發現，在臺灣人群中，除了已知的mα1等位基因外，其中上述6個氨基酸段中的第4個氨基酸殘基是S（SEQ ID NO:1），mα1也具有等位基因，其中第4個氨基酸殘基是C（SEQ ID NO:2）。顯然，這種新鑒定的等位基因僅存在於長同種型中，即mα1L中，而不存在於短同種型mα1S中（由於mα1S完全缺失了6個氨基酸拉伸物）。由於mα2僅作為短同種型存在，因此其膜外顯子中沒有等位基因變異。　　攜帶IgG和IgM的B細胞出現在發育早期，而攜帶IgA的B細胞在出生後約三個月首次出現。雖然在妊娠中期的早期通常可發現IgM和IgG漿細胞，但在妊娠第32周之前未觀察到產生IgA的細胞。血清IgA在出生時通常檢測不到，且直到青春期時才可達到成人血清濃度。在成人中，大多數人漿細胞都產生IgA。所產生的IgA比所有其他免疫球蛋白同種型的總和都多。　　正常血清中包括約80%的免疫球蛋白G（IgG），約15%的免疫球蛋白A（IgA），約5%的免疫球蛋白M（IgM），約0.2%的免疫球蛋白D（IgD），和痕量的免疫球蛋白E（IgE）。血漿IgA由骨髓中的B淋巴細胞和一些外周淋巴器官所產生。血漿IgA的半衰期為3-6天，而IgG的半衰期為21天。由於IgA的血漿濃度約為IgG的五分之一，這意味著血漿IgG和IgA的合成速率相似。　　分泌抗體的漿細胞及其直接前體（漿母細胞）在全身和粘膜免疫反應中產生。在任何未免疫的供體中，血漿母細胞和漿細胞總是可在人體血液中以低頻被檢測到。在這種穩態下，80%的漿母細胞和漿細胞表達免疫球蛋白A（IgA）。人骨髓中約40%的漿細胞是非遷移性的IgA，並表達β7整合素和CCR10，這表明粘膜漿細胞對駐留骨髓的長壽漿細胞有很大貢獻作用。全身疫苗接種不影響外周IgA漿母細胞數量，這表明粘膜和全身體液免疫應答相互獨立地受到調節（Blood (2009) 113:2461-2469）。抗 IgA 抗體在一個方面中，本發明提供了一種特異性結合膜IgA的抗體或其抗原結合片段。應當理解，如本發明所述的與膜IgA結合的抗體將具有多種應用。這些應用包括：用於生產檢測和診斷IgA相關病症的診斷試劑盒以及治療IgA相關病症。在這些情況下，可將這些抗體與診斷劑或治療劑聯繫起來、在競爭性測定中將它們用作捕獲劑或競爭劑、或單獨使用它們而不附加其他藥劑。如下面進一步所述，可突變或修飾所述抗體。 A. 一般方法　　製備和表徵抗體的方法是本領域熟知的（參見，例如，Antibodies:A Laboratory Manual, Cold Spring Harbor Laboratory, 1988；美國專利4,196,265）。用於生成單克隆抗體（MAb）的方法通常以與製備多克隆抗體相同的方式開始。這兩種方法的第一步均是使適當的宿主獲得免疫。如本領域眾所周知的，用於免疫的給定組合物的免疫原性可不同。因此，通常需要增強宿主免疫系統，這可以通過將肽或多肽免疫原偶聯到載體上來實現。示例性和優選的載體是匙孔血藍蛋白（KLH）和牛血清白蛋白（BSA）。也可使用其他白蛋白來作為載體，比如，卵清蛋白、小鼠血清白蛋白或兔血清白蛋白。用於將多肽與載體蛋白綴合的方法是本領域熟知的，並包括戊二醛、間-馬來醯亞胺基苯甲醯基-N-羥基琥珀醯亞胺酯、碳二亞胺和雙-雙氮聯苯胺。同樣如本領域所熟知的，通過使用免疫應答的非特異性刺激劑（稱為佐劑）可增強特定免疫原組合物的免疫原性。示例性和優選的佐劑包括完全弗氏佐劑（免疫應答的非特異性刺激劑（含有殺死的結核分枝桿菌））、不完全弗氏佐劑和氫氧化鋁佐劑。　　生成特異性結合膜IgA的抗體可能會因免疫接種宿主中IgA和IgA生成細胞的存在而變得複雜，該原因可能在B細胞成熟過程中負選擇IgA識別抗體。為了消除這種障礙，在一些實施方式中，將IgA缺陷型動物（比如，敲除IgA的小鼠）用於施行免疫。　　用於生產多克隆抗體的免疫原組合物的量隨著免疫原的性質以及用於免疫的動物的不同而不同。可使用多種途徑來施用免疫原（皮下、肌肉內、皮內、靜脈內和腹膜內）。可通過在免疫後的不同時間點對免疫動物的血液進行取樣來監測多克隆抗體的產生。還可給予第二次加強注射。重複加強和滴定的過程，直到達到合適的滴度。當獲得所需水準的免疫原性時，可將免疫的動物放血並分離和儲存血清，和/或可使用動物來生成MAb。　　免疫後，選擇具有產生抗體潛力的體細胞（特別是B淋巴細胞（B細胞））用於MAb生成方案。這些細胞可從活檢的脾臟或淋巴結或迴圈血液中獲得。然後將來自免疫動物中產生抗體的B淋巴細胞與永生骨髓瘤細胞的細胞融合，所述永生骨髓瘤細胞的細胞通常是與免疫的動物相同的種類之一或人或人/小鼠嵌合細胞。適於用在產生雜交瘤的融合程式中的骨髓瘤細胞系優選是非產生抗體的、具有高融合效率並具有因此產生的酶缺乏症，所述酶缺乏症使得生長不能在某些選擇性培養基中進行，這些培養基僅支持所需的融合細胞（雜交瘤）的生長。如本領域技術人員已知的，可使用許多骨髓瘤細胞中的任何一種（Goding, pp. 65-66, 1986; Campbell, pp. 75-83, 1984）。　　使產生抗體的脾或淋巴結細胞和骨髓瘤細胞進行雜交的方法通常包括：在促進細胞膜融合的一種或多種藥劑（化學或電學）的存在下，將體細胞與骨髓瘤細胞以2：1的比例混合（儘管該比例可分別從約20：1到約1：1變化）。Kohler和Milstein（1975；1976）描述了使用仙台病毒的融合方法，以及Gefter等人（1977）使用聚乙二醇（PEG）（比如，37%（v/v）PEG）的方法。使用電誘導融合方法也是合適的（Goding, pp. 71-74, 1986）。融合程式通常產生低頻率的活雜交體，約為1×10^-6 至1×10^-8 。然而，這不會造成問題，這是由於通過在選擇性培養基中培養，活的融合雜交體與親代的輸注細胞（特別是通常會繼續無限分裂的輸注的骨髓瘤細胞）不同。選擇性培養基通常是含有阻斷核苷酸從頭合成的試劑的組織培養基。示例性和優選的試劑是氨蝶呤、甲氨蝶呤和重氮絲氨酸。氨基喋呤和甲氨蝶呤阻斷嘌呤和嘧啶的從頭合成，而重氮絲氨酸僅阻斷嘌呤合成。當使用氨蝶呤或甲氨蝶呤時，培養基補充有次黃嘌呤和胸苷來作為核苷酸來源（HAT培養基）。在使用重氮絲氨酸的情況下，培養基補充有次黃嘌呤。如果B細胞來源於埃波斯坦巴爾（Epstein Barr）病毒（EBV）轉化的人B細胞系，則添加哇巴因，以消除未與骨髓瘤融合的EBV轉化的細胞系。　　優選的選擇性培養基是含有哇巴因的HAT或HAT。只有能夠操作核苷酸補救途徑的細胞才能在HAT培養基中存活。骨髓瘤細胞在補救途徑的關鍵酶（例如，次黃嘌呤磷酸核糖基轉移酶（HPRT））中是有缺陷的，因此它們無法存活。B細胞可操作補救途徑，但它們在培養中具有有限的壽命且通常在約兩周內死亡。因此，在選擇性培養基中能夠存活的細胞僅僅是由骨髓瘤和B細胞形成的雜交體。當用於融合的B細胞來源於一系列EBV轉化的B細胞時，哇巴因也用於雜交體的藥物選擇，這是因為EBV轉化的B細胞易受到藥物的殺傷，而選擇使用的骨髓瘤伴侶是抗哇巴的。　　從培養提供的雜交瘤群中可選擇特定的雜交瘤。通常，通過在微量滴定板中單克隆稀釋來培養細胞，然後通過測試各個克隆上清液（約2至3周後），可獲得所需的反應性來進行雜交瘤的選擇。該測定應該是靈敏、簡單且快速的，比如，放射免疫測定、酶免疫測定、細胞毒性測定、噬斑測定點免疫結合測定等。然後通過流式細胞術分選將選擇的雜交瘤連續稀釋或分選單細胞，並克隆到單個生成抗體的細胞系中，然後可進行無限繁殖克隆以提供mAb。可通過兩種基本方式利用細胞系進行MAb生產。可將雜交瘤樣品注射到動物（例如，小鼠）中（通常進入腹膜腔）。任選地，在注射之前，用烴（尤其是諸如姥鮫烷（四甲基十五烷）的油）對動物進行引發。當以這種方式使用人雜交瘤時，最好注射免疫受損的小鼠（比如，SCID小鼠），以避免腫瘤排斥。注射的動物產生分泌出由融合細胞雜交體產生的特異性單克隆抗體的腫瘤。然後可收集動物的體液（比如，血清或腹水），以提供高濃度的MAb。單個細胞系也可在體外培養，其中MAb天然地分泌到培養基中，從中可容易地獲得高濃度的MAb。或者，可在體外使用人雜交瘤細胞系以在細胞上清液中產生免疫球蛋白。細胞系可改造為在無血清培養基中生長，以優化回收高純度人單克隆免疫球蛋白的能力。　　如果需要，通過任一方法產生的MAb都可使用過濾、離心和各種色譜方法（比如，FPLC）或親和色譜法來進行進一步純化。本發明的單克隆抗體的片段可通過包括酶（比如，胃蛋白酶或木瓜蛋白酶）消化和/或化學還原裂解二硫鍵的方法從純化的單克隆抗體獲得。或者，可使用自動肽合成儀來合成本發明所涵蓋的單克隆抗體片段。　　分子克隆方法也可用于產生單克隆抗體。為此，可從雜交瘤系中分離RNA，並通過RT-PCR獲得抗體基因，以及將其克隆到免疫球蛋白表達載體中。或者，以從細胞系分離的RNA來製備組合免疫球蛋白噬菌粒文庫，並通過使用病毒抗原淘選來選擇表達適當抗體的噬菌粒。與常規雜交瘤技術相比，該方法的優點在於：可在單輪中產生和篩選約10⁴ 倍的抗體，並可通過H和L鏈組合產生新的特異性，這樣可進一步增加了找到合適抗體的機會。　　其他美國專利（每個都作為參考文獻併入本發明）教導了本發明中有用抗體的生產，其中美國專利5,565,332描述了使用組合方法來生產嵌合抗體；美國專利4,816,567描述了重組免疫球蛋白製劑；美國專利4,867,973描述了抗體-治療劑綴合物。 B. 膜IgA的抗體　　由於血清和粘膜中有豐富IgA且IgA作為第一道防線在抵抗病原體具備重要功能，所以發現和開發出可針對膜錨定IgA但無法結合可溶性IgA的抗體是至關重要的。因此，此類抗體的表位元需要僅存在於膜錨定IgA上，而不存在於可溶性IgA中。　　膜錨定形式的人IgA（也稱為膜IgA或mIgA）與可溶性IgA的不同之處在於：膜錨定形式的重鏈具有從CH3結構域延伸出的三個額外結構域，即細胞外膜近端結構域（EMPD）、跨膜結構域（TMD）和細胞質結構域（CytoD）。因此，在一些實施方式中，本發明所述的抗體或其抗原結合片段特異性結合於EMPD、TMD或CytoD中的表位。在優選實施方式中，本發明所述的抗體或其抗原結合片段特異性結合EMPD中的表位。在一個實施方式中，本發明所述的抗體或其抗原結合片段特異性結合IgA 1的EMPD中的表位。在一個實施方式中，本發明所述的抗體或其抗原結合片段特異性結合IgA 2的EMPD中的表位。在一個實施方式中，本發明所述的抗體或其抗原結合片段特異性結合於均可在IgA1的EMPD和IgA2的EMPD中發現的表位。　　IgA 1重鏈（mα1）以短和長同種型而存在，稱為mα1S和mα1L，後者在細胞外區段（EMPD結構域）的N-末端含有額外的6個氨基酸殘基GSCSVA。經調查發現，在臺灣人群中，除了已知的mα1等位基因（其中上述6個氨基酸拉伸物中的第4個氨基酸殘基是S）外，mα1也具有等位基因，其中第4個氨基酸殘基是C。這種新鑒定的等位基因僅存在於長同種型中，即mα1L中，而不存在於短同種型mα1S中（由於mα1S完全缺失了6個氨基酸拉伸物）。相反，IgA 2的重鏈（mα2）僅作為短同種型存在，且其膜外顯子中沒有等位基因變異。　　在某些實施方式中，本發明提供的抗體和抗體結合片段能夠特異性結合膜IgA，同時通過等離子體共振結合測定法測定，結合親和力約為10^-6 M或更低（例如，10^-6 M、10^-8 M、10^-9 M、10^-10 M、10^-11 M、10^-12 M、10^-13 M）。結合親和力可由K_D 值表示，該值被計算為當抗原和抗原結合分子之間的結合達到平衡時解離速率與結合速率的比率（k_off /k_on ）。抗原結合親和力（例如，K_D ）可使用本領域已知的合適方法來適當地確定，例如，該方法包括使用諸如Biacore的儀器進行的等離子體共振結合測定法（參見，例如，Murphy等人，Current protocols in protein science, Chapter 19, unit 19.14, 2006）。　　在某些實施方式中，本發明提供的抗體和抗體結合片段能夠結合IgA，通過ELISA測定，所述IgA具有0.001 μg/ml-1μg/ml（例如，0.001μg/ml-0.5μg/ml、0.001 μg/ml-0.2μg/ml、0.001μg/ml-0.1μg/ml、0.01μg/ml-0.2μg/ml、0.01μg/ml-0.1μg/ml、0.01μg/ml-0.05μg/ml、0.01μg/ml-0.03μg/ml或0.001μg/ml-0.01μg/ml）的EC₅₀ （即50%結合濃度），或通過FACS測定，具有0.01μg/ml-1μg/ml（例如，0.01μg/ml-0.5μg/ml、0.01μg/ml-0.2μg/ml、0.05μg/ml-1μg/ml、0.05μg/ml-0.5μg/ml或0.05μg/ml-0.2μg/ml）的EC₅₀ 。抗體與膜IgA的結合可通過本領域已知的方法來測定，所述方法如ELISA、FACS、表面等離子體共振、GST下拉、表位標籤、免疫沉澱、Far-western印跡、螢光共振能量轉移、時間分辨螢光免疫分析（TR-FIA）、放射免疫分析（RIA）、酶免疫分析、乳膠凝集、蛋白質印跡和免疫組織化學或其他結合試驗法。在一個示例性實施方式中，在洗去未結合的抗體後，使測試抗體（即第一抗體）與固定的mIgA或表達mIgA的細胞結合，並引入標記的第二抗體，所述標記的第二抗體可結合於已結合的第一抗體並因此實現對其的檢測。當使用固定的mIgA時，可用酶標儀來進行檢測，或當使用表達mIgA的細胞時，可通過使用FACS分析來進行檢測。　　在某些實施方式中，當向受試者施用本發明所述抗體或抗體結合片段，本發明所述抗體或抗體結合片段可消除或減少表達IgA的細胞或阻斷所述受試者（或所述受試者中的癌症微環境）中表達IgA的B細胞的活化或免疫抑制功能。在一些實施方式中，至少50%、至少60%、至少70%、至少80%或至少90%的表達IgA的B細胞在所述受試者中（或所述受試者中的癌症微環境）被消除。在一些實施方式中，本發明所述抗體或抗體結合片段可阻斷表達IgA的B細胞中至少50%、至少60%、至少70%、至少80%或至少90%的活性或免疫抑制性功能。　　在一些實施方式中，所述抗體消除或減少IgA陽性漿細胞。在一些實施方式中，所述抗體消除或減少IgA陽性漿細胞。在一些實施方式中，所述抗體消除或減少IgA轉換的B細胞。在一些實施方式中，所述抗體消除或減少IgA漿母細胞。在一些實施方式中，所述抗體消除或減少IgA記憶B細胞。　　雖然本發明的抗體是作為IgG的抗體產生的，但修飾恒定區以改變其功能可能是有用的。抗體的恒定區通常介導抗體與宿主組織或因數的結合，該宿主組織或因數包括免疫系統的各種細胞（例如，效應細胞）和經典補體系統的第一組分（Clq）。因此，術語“抗體”包括IgA、IgG、IgE、IgD、IgM型的完整免疫球蛋白（及其亞型），其中免疫球蛋白的輕鏈可以是κ或λ類型。在輕鏈和重鏈內，可變區和恒定區通過約12個或更多個氨基酸的“J”區連接，同時重鏈還包括約10個以上氨基酸的“D”區。通常參見Fundamental Immunology Ch. 7 (Paul, W., ed., 2^nd ed. Raven Press, N.Y. 1989)。 C. 抗體工程　　在各種實施方式中，可出於各種原因來選擇設計鑒定的抗體的序列，比如，改善的表達、改善的交叉反應性或減少的脫靶結合。以下是對抗體工程相關技術的一般性討論。　　可培養雜交瘤，然後裂解細胞，並提取總RNA。隨機六核苷酸可與RT一起使用以生成RNA的cDNA拷貝，然後使用預期對所有人可變基因序列擴增的PCR引物的多重混合物來進行PCR。可將PCR產物克隆到pGEM-T Easy載體中，然後使用標準載體引物通過自動DNA測序來進行測序。可使用從雜交瘤上清液收集的抗體來進行對結合和中和的測定，並使用蛋白G柱通過FPLC來進行純化。可通過將重鏈和輕鏈Fv DNA從克隆載體亞克隆到IgG質粒載體中、轉染到HEK293細胞或CHO細胞中並從HEK293或CHO細胞上清液中收集和純化抗體來生成重組全長IgG抗體。　　使用與最終cGMP製造過程相同的宿主細胞和細胞培養過程快速產生抗體可以縮短過程開發程式的時間。　　抗體分子包括單價的抗體衍生物，例如通過mAb的蛋白水解切割產生的片段（例如F(ab’)，F(ab’)₂ ），或包含例如通過重組方法產生的單鏈免疫球蛋白。在一個實施方式中，這些片段可彼此進行組合，或與其他抗體片段或受體配體進行組合以形成“嵌合”結合分子。值得注意的是，此類嵌合分子可含有能夠結合于相同分子的不同表位的取代基。抗體結合修飾　　在相關實施方式中，抗體是所公開的抗體的衍生物，例如，包含與公開的抗體中的CDR序列相同的CDR序列的抗體（例如，嵌合或CDR-移植的抗體）。或者，可能希望進行修飾，比如，將保守變化引入抗體分子中。在進行這種改變時，可考慮氨基酸的親水指數。在本領域中通常可以理解親水氨基酸指數在賦予蛋白質相互作用生物學功能方面的重要性（Kyte和Doolittle，1982）。可接受的是，氨基酸的相對親水特性有助於所得蛋白質的二級結構，這又決定了蛋白質與其他分子（例如，酶、底物、受體、DNA、抗體、抗原等等）的相互作用。　　本領域中還應理解，可基於親水性來有效地取代相似的氨基酸。通過引用併入本發明的美國專利No.4,554,101指出：蛋白質的最大局部平均親水性（由其相鄰氨基酸的親水性決定）與蛋白質的生物學性質相關。如美國專利No.4,554,101詳述，下列親水性值已指定給氨基酸殘基：鹼性氨基酸：精氨酸（+3.0）、賴氨酸（+3.0）和組氨酸（-0.5）；酸性氨基酸：天冬氨酸（+3.0±1）、谷氨酸（+3.0±1）、天冬醯胺（+0.2）和穀氨醯胺（+0.2）；親水性非離子氨基酸：絲氨酸（+0.3）、天冬醯胺（+0.2）、穀氨醯胺（+0.2）和蘇氨酸（-0.4）、含硫氨基酸：半胱氨酸（-1.0）和蛋氨酸（-1.3）；疏水性非芳香族氨基酸：纈氨酸（-1.5）、亮氨酸（-1.8）、異亮氨酸（-1.8）、脯氨酸（-0.5±1）、丙氨酸（-0.5）和甘氨酸（0）；疏水性芳香族氨基酸：色氨酸（-3.4）、苯丙氨酸（-2.5）和酪氨酸（-2.3）。　　應理解，氨基酸可取代為具有相似親水性的另一種氨基酸，並產生生物學或免疫學修飾的蛋白質。在這些變化中，優選親水性值在±2內的氨基酸來進行取代，特別優選在±1內的氨基酸來進行取代，甚至更特別優選在±0.5內的氨基酸來進行取代。　　如上所述，氨基酸取代通常基於氨基酸側鏈取代基的相對相似性，例如，它們的疏水性、親水性、電荷、大小等。考慮到各種前述特徵情況下的示例性取代是本領域技術人員公知的，這包括：精氨酸和賴氨酸；谷氨酸和天冬氨酸；絲氨酸和蘇氨酸；穀氨醯胺和天冬醯胺；以及纈氨酸、亮氨酸和異亮氨酸。　　本發明還考慮到同種型修飾。通過將Fc區修飾為具有不同的同種型，可實現不同的功能。例如，改變為IgG₁ 可增加抗體依賴性細胞的細胞毒性，切換到A型可改善組織分佈，且切換到M型則可改善效價。　　經修飾的抗體可通過本領域技術人員已知的任何技術來製備，這些技術包括通過標準分子生物學技術表達或多肽的化學合成。用於重組表達的方法在本檔的其他地方提到。 Fc區修飾　　通常為了改變抗體的一個或多個功能特性，比如，血清半衰期、補體結合、Fc受體結合和/或效應功能（例如，抗原依賴性細胞毒性），本發明公開的抗體還可被工程化以包括Fc區內的修飾。此外，本發明公開的抗體可以是經化學修飾的（例如，一個或多個化學部分可連接到抗體上）或者可被修飾成改變其糖基化、被再次修飾成改變抗體的一種或多種功能特性。下面詳細討論了這些實施方式中的每一個實施方式。Fc區中殘基的編號是Kabat的EU索引的編號。本發明公開的抗體還包括具有修飾的（或阻斷的）Fc區的抗體，以提供改變的效應子功能。參見，例如，美國專利5,624,821；WO2003/086310；WO2005/120571；WO2006/0057702。此種修飾可用于增強或抑制免疫系統的各種反應，同時在診斷和治療中可能具有有益效果。Fc區的改變包括氨基酸改變（取代、缺失和插入）、糖基化或去糖基化（去糖基化也可稱為無糖基化）以及添加多個Fc。對Fc的改變還可改變治療性抗體中抗體的半衰期，使得施用頻率降低，從而增加了便利性並減少了材料的使用。據報導，這種突變消除了鉸鏈區中重鏈間二硫鍵的異質性。　　在一個實施方式中，CH1的鉸鏈區被修飾成使得鉸鏈區中半胱氨酸殘基的數量增加或減少。該方法在美國專利5,677,425中進一步被描述。CH1鉸鏈區中半胱氨酸殘基的數量被改變，例如，以促進輕鏈和重鏈的組裝或增加或降低抗體的穩定性。在另一個實施方式中，修飾抗體以增加其生物半衰期。各種方法都是可能的。例如，可引入以下突變中的一種或多種：如美國專利6,277,375所述的T252L、T254S、T256F。或者，為了增加生物半衰期，可在CH1或CL區內將抗體改變成包含取自IgG的Fc區的CH2結構域的兩個環的補救受體結合表位，如美國專利5,869,046和6,121,022所述。在又一個實施方式中，通過使用不同的氨基酸殘基取代至少一個氨基酸殘基來改變Fc區，以改變抗體的效應子功能。例如，可使用不同的氨基酸殘基來替換選自氨基酸殘基234、235、236、237、297、318、320和322的一個或多個氨基酸，使得抗體對效應配體具有改變的親和力，但保留了親本抗體的抗原結合能力。例如，需改變親和力的效應配體可以是Fc受體或補體的C1組分。該方法在美國專利5,624,821和5,648,260中進一步被描述。　　在另一個實施方式中，改變氨基酸位置231和239內的一個或多個氨基酸殘基，從而改變抗體固定補體的能力。該方法在PCT公開WO 94/29351中進一步被描述。在又一個實施方式中，通過修飾以下位置的一個或多個氨基酸，Fc區被修飾成增加或降低抗體介導抗體依賴性細胞毒性（ADCC）的能力和/或修飾成增加或降低抗體對Fcγ受體的親和力：238、239、243、248、249、252、254、255、256、258、264、265、267、268、269、270、272、276、278、280、283、285、286、289、290、292、293、294、295、296、298、301、303、305、307、309、312、315、320、322、324、326、327、329、330、331、333、334、335、337、338、340、360、373、376、378、382、388、389、398、414、416、419、430、434、435、437、438或439。該方法在PCT公開WO 00/42072中進一步被描述。此外，已繪出了人IgG1上FcγR1、FcγRII、FcγRIII和FcRn的結合位點，並已描述了具有改善的結合的變體。位置256、290、298、333、334和339處的特異性突變被顯示出，以改善與FcγRIII結合。另外，顯示出以下組合突變，以改善FcγRIII結合：T256A/S298A、S298A/E333A、S298A/K224A和S298A/E333A/K334A。　　在一個實施方式中，通過修飾殘基243和264，Fc區被修飾成降低抗體介導效應子功能和/或增加抗炎特性的能力。在一個實施方式中，通過將位置243和264處的殘基改變成丙氨酸來修飾抗體的Fc區。在一個實施方式中，通過修飾殘基243、264、267和328，Fc區被修飾成降低抗體介導效應子功能和/或增加抗炎特性的能力。在又一個實施方式中，抗體包含特定的糖基化模式。例如，可製備無糖基化的抗體（即，抗體缺乏糖基化）。例如，抗體的糖基化模式可被改變成增加抗體對抗原的親和力或親合力。例如，這種修飾可通過改變抗體序列中的一個或多個糖基化位點來實現。例如，可進行一個或多個氨基酸取代導致一個或多個可變區框架去除糖基化位點，從而消除該位點的糖基化。這種糖基化可增加抗體對抗原的親和力或親合力。參見，例如，美國專利5,714,350和6,350,861。　　還可製備一種抗體，其中糖基化模式包括低岩藻糖基化或非岩藻糖基化的聚糖，比如，低岩藻糖基化的抗體或非岩藻糖基化的抗體在聚糖上具有減少量的岩藻糖基殘基。這些抗體還可包括具有增加量的GlcNac二分枝結構的聚糖。已經證明這種改變的糖基化模式增加了抗體的ADCC能力。例如，這種修飾可通過在宿主細胞中表達抗體來實現，其中糖基化途徑已得到基因工程改造而產生具有特定糖基化模式的糖蛋白。這些細胞已在本領域中得到描述並可用作表達本發明的重組抗體的宿主細胞，從而產生具有改變的糖基化的抗體。例如，細胞系Ms704、Ms705和Ms709缺乏岩藻糖基轉移酶基因FUT8（α（1,6）-岩藻糖基轉移酶），從而在Ms704、Ms705和Ms709細胞系中表達的抗體可在其糖基上缺乏岩藻糖。Ms704、Ms705和Ms709 FUT8-/-細胞系是通過使用兩個替換載體靶向破壞CHO/DG44細胞中的FUT8基因而產生的（參見，美國專利公開20040110704）。作為另一個實施方式，EP 1 176 195描述了具有功能性破壞的FUT8基因的細胞系，該FUT8基因編碼岩藻糖基轉移酶，從而在這種細胞系中表達的抗體可通過減少或消除α-1，6鍵相關酶來表現出低岩藻糖基化。EP 1 176 195還描述了具有低酶活性或無酶活性的細胞系（例如大鼠骨髓瘤細胞系YB2/0（ATCC CRL 1662）），該酶活性用於向與抗體Fc區結合的N-乙醯葡糖胺中添加岩藻糖。PCT公開WO 03/035835描述了變體CHO細胞系Lec13細胞，該細胞具有降低的將岩藻糖與Asn（297）-連接的糖基連接的能力，同時也導致在該宿主細胞中表達的抗體產生低岩藻糖基化。如PCT公開WO 06/089231中所述，也可在雞蛋中產生具有修飾的糖基化譜的抗體。或者，可在植物細胞中產生具有修飾的糖基化譜的抗體，比如，Lemna（美國專利7,632,983）。美國專利6,998,267和7,388,081公開了在植物系統中產生抗體的方法。PCT公開WO 99/54342描述了經工程改造以表達糖蛋白修飾糖基轉移酶（例如，β（1,4）-N-乙醯葡糖胺基轉移酶III（GnTIII））的細胞系，從而在工程化的細胞系中表達的抗體表現出增加的GlcNac二分枝結構，導致抗體增加了ADCC活性。　　或者，可使用岩藻糖苷酶來切割抗體的岩藻糖殘基；例如，岩藻糖苷酶α-L-岩藻糖苷酶從抗體中除去岩藻糖基殘基。本發明公開的抗體還包括在低等真核生物宿主細胞，特別是真菌宿主細胞（比如，酵母和絲狀真菌）中產生的抗體，這些宿主細胞已經過基因工程改造來產生具有哺乳動物或人樣糖基化模式的糖蛋白。這些基因修飾的宿主細胞相對於目前使用的哺乳動物細胞系的特別優勢在於能夠控制細胞中產生的糖蛋白的糖基化譜，從而可產生糖蛋白的組合物，其中特定的N-聚糖結構佔據優勢（參見，例如，美國專利7,029,872和7,449,308）。這些經基因修飾的宿主細胞已用於產生主要具有特定N-聚糖結構的抗體。　　此外，由於酵母或絲狀真菌等真菌缺乏產生岩藻糖基化糖蛋白的能力，所以除非細胞被進一步修飾成包括產生岩藻糖基化糖蛋白的酶促途徑，否則在這些細胞中產生的抗體將缺乏岩藻糖（參見，例如，PCT公開WO 2008112092）。在特定實施方式中，本發明公開的抗體還包括在低等真核宿主細胞中產生的抗體，該抗體包含岩藻糖基化和非岩藻糖基化的雜合和複合N-聚糖，包括二分枝和多分枝糖基，包括但不限於N-聚糖，比如，GlcNAc(1-4)Man3GlcNAc2；Gal(1-4)GlcNAc(1-4)Man3GlcNAc2；NANA(1-4)Gal(1-4)GlcNAc(1-4)Man3GlcNAc2。在特定實施方式中，本發明提供的抗體可具有至少一種選自GlcNAcMan5GlcNAc2、GalGlcNAcMan5GlcNAc2和NANAGalGlcNAcMan5GlcNAc2的雜合N-聚糖。在特定方面中，雜合N-聚糖是組合物中主要的N-聚糖種類。在其他方面中，雜合N-聚糖是特定的N-聚糖種類，該聚糖種類包含組合物中約30%、40%、50%、60%、70%、80%、90%、95%、97%、98%、99%或100的雜合N-聚糖%。　　在特定實施方式中，本發明提供的抗體具有至少一種選自GlcNAcMan3GlcNAc2、GalGlcNAcMan3GlcNAc2、NANAGalGlcNAcMan3GlcNAc2、GlcNAc2Man3GlcNAc2、GalGlcNAc2Man3GlcNAc2、Gal2GlcNAc2Man3GlcNAc2、NANAGal2GlcNAc2Man3GlcNAc2和 NANA2Gal2GlcNAc2Man3GlcNAc2的複合N-聚糖。在特定方面中，複合N-聚糖是組合物中主要的N-聚糖種類。在其他方面中，複合N-聚糖是特定的N-聚糖種類，該聚糖種類包含組合物中約30%、40%、50%、60%、70%、80%、90%、95%、97%、98%、99%或100的複合N-聚糖%。在特定實施方式中，N-聚糖是岩藻糖化的。通常，岩藻糖在N-聚糖的還原端與GlcNAc形成α1,3-鍵、在N-聚糖的還原端與GlcNAc形成α1,6-鍵、在N-聚糖的非還原端與Gal形成α1,2-鍵、在N-聚糖的非還原端與GlcNac的α1,3-鍵，或在N-聚糖的非還原端的與GlcNAc形成α1,4-鍵。　　因此，在上述糖蛋白組合物的特定方面中，糖型為α1,3-鍵或α1,6-鏈岩藻糖，以產生選自Man5GlcNAc2(Fuc)、GlcNAcMan5GlcNAc2(Fuc)、Man3GlcNAc2(Fuc)、 GlcNAcMan3GlcNAc2(Fuc)、GlcNAc2Man3GlcNAc2(Fuc)、GalGlcNAc2Man3GlcNAc2(Fuc)、Gal2GlcNAc2Man3GlcNAc2(Fuc)、NANAGal2GlcNAc2Man3GlcNAc2(Fuc)和NANA2Gal2GlcNAc2Man3GlcNAc2(Fuc)中的糖型；糖型為α1,3-鍵或α1,4-鍵，以產生選自GlcNAc(Fuc)Man5GlcNAc2、GlcNAc(Fuc)Man3GlcNAc2、 GlcNAc2(Fuc1-2)Man3GlcNAc2、 GalGlcNAc2(Fuc1-2)Man3GlcNAc2、 Gal2GlcNAc2(Fuc1-2)Man3GlcNAc2、NANAGal2GlcNAc2(Fuc1-2)Man3GlcNAc2和NANA2Gal2GlcNAc2(Fuc1-2)Man3GlcNAc2中的糖型；或糖型為α1,2-鍵岩藻糖，以產生選自Gal(Fuc)GlcNAc2Man3GlcNAc2、 Gal2(Fuc1-2)GlcNAc2Man3GlcNAc2、 NANAGal2(Fuc1-2)GlcNAc2Man3GlcNAc2和NANA2Gal2(Fuc1-2)GlcNAc2Man3GlcNAc2中的糖型。　　在其他方面中，抗體包含高甘露糖N-聚糖，其包括但不限於Man8GlcNAc2、Man7GlcNAc2、Man6GlcNAc2、Man5GlcNAc2、Man4GlcNAc2或由Man3GlcNAc2 N-聚糖結構組成的N-聚糖。在上述其他方面中，複合N-聚糖還包括岩藻糖基化和非岩藻糖基化的二分枝和多分枝種類。如本發明所用的術語“N-聚糖”和“糖型”可互換使用，並指N-連接的寡糖，例如，通過天冬醯胺-N乙醯葡糖胺鍵與多肽的天冬醯胺殘基連接的寡糖。N-連接的糖蛋白含有與蛋白質中天冬醯胺殘基的醯胺氮連接的N-乙醯葡糖胺殘基。 D. 抗體的純化　　在某些實施方式中，可對本發明的抗體進行純化。如本發明所用的術語“純化”意指組合物可與其他組分分離，其中蛋白質相對于其天然可獲得的狀態被純化至任何程度。因此，純化的蛋白質也指脫離其天然產生的環境的蛋白質。當使用術語“基本上純化”時，該名稱是指組合物中蛋白質或肽形成了該組合物的主要組分，例如，在該組合物構成約50%、約60%、約70%、約80%、約90%、約95%或更多的蛋白質。　　蛋白質純化技術是本領域技術人員熟知的。這些技術在一個層面上涉及細胞環境對多肽和非多肽級分的粗分級分離。將多肽與其他蛋白質分離後，可使用色譜和電泳技術進一步純化目標多肽，以實現部分或完全純化（或純化至同質性）。特別適於製備純肽的分析方法是離子交換色譜法、排阻色譜法、聚丙烯醯胺凝膠電泳法、等電聚焦法。其他用於蛋白質純化的方法包括：用硫酸銨、PEG、抗體等或通過熱變性進行沉澱，然後進行離心；凝膠進行過濾、反相、羥基磷灰石和親和色譜方法；以及這些和其他技術的組合。　　在純化本發明的抗體時，可能需要在原核或真核表達系統中表達多肽並使用變性條件來提取蛋白質。可使用親和柱純化來自其他細胞組分的多肽，所述親和柱與多肽的標記部分結合。如本領域通常已知的，可改變進行各種純化步驟的順序，或者可省略某些步驟，並仍然產生用於製備基本上純化的蛋白質或肽的合適方法。　　通常，使用與抗體Fc部分結合的試劑（即蛋白A）來分離完整抗體。或者，可使用抗原同時純化和選擇合適的抗體。這些方法通常利用與載體（比如，柱、篩檢程式或珠子）結合的選擇劑。抗體與載體結合，去除污染物（例如，洗掉）並通過施加條件（鹽，熱等）釋放抗體。　　根據本發明，用於量化蛋白質或肽的純化程度的各種方法對於本領域技術人員而言是已知的。例如，這些包括：確定活性餾分的比活性或通過SDS/PAGE分析來評估餾分內多肽的量。評估餾分純度的另一種方法是：計算餾分的比活性，將其與初始提取物的比活性進行比較，從而計算純度。當然，用於表示活性量的實際單位取決於選擇用於純化的特定測定技術以及表達的蛋白質或肽是否表現出可檢測的活性。　　已知多肽的遷移可隨SDS/PAGE的不同條件而變化，有時是顯著的（Capaldi等人，1977）。因此應理解，在不同的電泳條件下，純化或部分純化的表達產物的表觀分子量會出現變化。抗體組合物 本發明在另一個方面中提供包含與膜結合IgA特異性結合的抗體的組合物。這些組合物包含藥物組合物和抗體偶聯物，例如，用於診斷或治療目的。 A. 藥物組合物　　本發明提供的藥物組合物包含預防或治療有效量的抗體或其片段以及藥學上可接受的載體。在具體實施方式中，術語“藥學上可接受的”是指聯邦或州政府的管理機構批准的或在美國藥典或其他公認的藥典中列出用於動物（更特別是人）的。　　術語“載體”是指與治療劑一起施用的稀釋劑、賦形劑或載劑。此類藥物載體可以是無菌液體（比如，水和油），包括石油、動物、植物或合成來源的那些（比如，花生油、大豆油、礦物油、芝麻油等）。當靜脈內施用藥物組合物時，水是特定的載體。鹽水溶液和葡萄糖水溶液以及甘油溶液也可用作液體載體，特別是用於可注射溶液。載體的其他合適組分可包括，例如，抗氧化劑、保濕劑、填充劑、粘合劑、崩解劑、緩衝劑、防腐劑、潤滑劑、調味劑、增稠劑、著色劑、乳化劑或穩定劑（比如，糖和環糊精）。合適的抗氧化劑可包括，例如，甲硫氨酸、抗壞血酸、EDTA、硫代硫酸鈉、鉑、過氧化氫酶、檸檬酸、半胱氨酸、硫代甘油、巰基乙酸、硫代山梨醇、丁基化羥基苯甲醚、丁基化羥基甲苯和/或沒食子酸丙酯。如本文所公開的，在包含本發明提供的抗體或抗原結合片段以及綴合物的組合物中包含一種或多種抗氧化劑（比如，甲硫氨酸）可減少抗體或抗原結合片段的氧化現象。氧化的減少防止或減少了結合活性或結合親和力的喪失，從而改善抗體穩定性和最大化保質期。因此，在某些實施方式中，提供的組合物包含一種或多種本發明公開的抗體或抗原結合片段以及一種或多種抗氧化劑（比如，甲硫氨酸）。還提供了用於避免本發明提供的抗體或抗原結合片段的氧化、延長其保質期和/或改善其功效的方法，所述方法通過將抗體或抗原結合片段與一種或多種抗氧化劑（比如，蛋氨酸）混合來完成。合適的保濕劑包括乙二醇、甘油或山梨糖醇。合適的潤滑劑包括，例如，乙醯酯蠟、氫化植物油、硬脂酸鎂、硬脂酸甲酯、礦物油、聚氧乙烯-聚氧丙烯共聚物、聚乙二醇、聚乙烯醇、十二烷基硫酸鈉或白蠟或其中兩種或多種的混合物。合適的乳化劑包括卡波姆、聚氧乙烯-20-硬脂基醚、十六十八醇、十六醇、膽固醇、硬脂酸二甘醇酯、硬脂酸甘油酯、羥丙基甲基纖維素、羊毛脂、聚氧乙烯十二烷基醚、甲基纖維素、聚氧乙烯硬脂酸酯、聚山梨醇酯、丙二醇單硬脂酸酯、脫水山梨糖醇酯或硬脂酸。　　為了進一步說明，藥學上可接受的載體可包括，例如，含水載體（比如，氯化鈉注射液、林格氏注射液、等滲葡萄糖注射液、無菌注射水或右旋糖和乳酸林格氏注射液）、非水性載體（比如，植物來源的固定油、棉籽油、玉米油、芝麻油或花生油、抑菌或抑菌濃度的抗菌劑）、等滲劑（比如，氯化鈉或葡萄糖）、緩衝液（比如，磷酸鹽或檸檬酸鹽緩衝液）、抗氧化劑（比如，硫酸氫鈉）、局部麻醉劑（比如，鹽酸普魯卡因）、懸浮劑和分散劑（比如，羧甲基纖維素鈉、羥丙基甲基纖維素或聚乙烯吡咯烷酮）、乳化劑（比如，聚山梨醇酯80（TWEEN-80））、螯合劑（比如，EDTA（乙二胺四乙酸）或EGTA（乙二醇四乙酸）、乙醇、聚乙二醇、丙二醇、氫氧化鈉、鹽酸、檸檬酸或乳酸）。用作載體的抗微生物劑可以多劑量容器的形式加入到藥物組合物中，所述載體包括酚類或甲酚類、汞、苄醇、氯丁醇、對羥基苯甲酸甲酯和對羥基苯甲酸甲酯、硫柳汞、苯紮氯銨和苄索氯銨。合適的賦形劑可包括，例如，水、鹽水、右旋糖、甘油或乙醇。合適的無毒輔助物質可包括，例如，潤濕劑或乳化劑、pH緩衝劑、穩定劑、溶解度增強劑或諸如乙酸鈉、脫水山梨糖醇單月桂酸酯、三乙醇胺油酸酯或環糊精的試劑。　　藥物組合物可以是液體溶液、懸浮液、乳液、洗劑、泡沫、丸劑、膠囊、片劑、緩釋製劑、軟膏、乳膏、糊劑、凝膠、噴霧劑、氣霧劑或粉末。口服製劑可包括標準載體，比如，藥物級甘露醇、乳糖、澱粉、硬脂酸鎂、聚乙烯吡咯烷酮、糖精鈉、纖維素、碳酸鎂等。　　在某些實施方式中，將藥物組合物配製成可注射的組合物。可注射藥物組合物可製備成任何常規形式，例如，液體溶液、懸浮液、乳液或適於產生液體溶液、懸浮液或乳液的固體形式。注射劑的製劑可包括即用於注射的無菌和/或非熱解溶液、即將在使用前與溶劑混合的無菌乾燥可溶性產品（比如，凍幹粉末），包括皮下注射片劑，即用於注射的無菌懸浮液、即將在使用前與載體混合的無菌乾燥不溶性產品以及無菌和/或非熱解乳液。這些溶液可以是水溶液或非水溶液。　　在某些實施方式中，單位劑量腸胃外製劑包裝在安瓿、小瓶或帶針頭的注射器中。如本領域已知和實踐的，腸胃外施用的所有制劑應該是無菌的而不是熱解的。　　在某些實施方式中，通過將如本發明公開的抗體或抗原結合片段溶解在合適的溶劑中來製備無菌的凍幹粉末。該溶劑可含有賦形劑，該賦形劑改善了由粉末製備的粉末或重構溶液的穩定性或其它藥理學組分。可使用的賦形劑包括但不限於水、右旋糖、山梨糖醇、果糖、玉米糖漿、木糖醇、甘油、葡萄糖、蔗糖或其他合適的試劑。在一個實施方式中，該溶劑可含有約為中性pH的緩衝劑，比如，檸檬酸鹽、磷酸鈉或磷酸鉀或本領域技術人員已知的其他此類緩衝劑。隨後對溶液進行無菌過濾，然後在本領域技術人員已知的標準條件下凍幹，得到所需的製劑。在一個實施方式中，將得到的溶液分配到小瓶中進行凍幹。每個小瓶可含有單劑量或多劑量的抗IgA抗體或其抗原結合片段或其組合物。對於一劑或一組劑量（例如，約10%）所需的少量過量填充小瓶是可接受的，以便於準確取樣和精確定量施用。凍幹粉末可在適當的條件下儲存，比如，在約4℃至室溫下儲存。　　使用注射用水對凍幹粉末的重構提供了用於腸胃外施用的製劑。在一個實施方式中，為了重構，將無菌和/或非熱解水或其他液體合適的載體加入到凍幹粉末中。精確的量取決於所選擇的療法，並可憑經驗來確定。 B. 抗體綴合物　　本發明的抗體可與至少一種試劑連接以形成抗體綴合物。為了增加抗體分子作為診斷劑或治療劑的功效，通常將至少一個所需分子或部分連接或共價結合或複合。這種分子或部分可以是，但不限於，至少一種效應分子或報導分子。效應分子包含具有所需活性（例如，細胞毒活性）的分子。附著于抗體的效應分子的非限制性實施方式包括毒素、抗腫瘤劑、治療性酶、放射性核素、抗病毒劑、螯合劑、細胞因數、生長因數和寡核苷酸或多核苷酸。相反，報導分子定義為任何可使用測定法檢測的部分。與抗體綴合的報告分子的非限制性實施方式包括酶、放射性標記、半抗原、螢光標記、磷光分子、化學發光分子、發色團、光親和分子、有色顆粒或配體（比如，生物素）。　　抗體綴合物通常優選用作診斷劑。抗體診斷通常屬於兩類，用於體外診斷的那些（比如，用於各種免疫測定）以及用於體內診斷方案的那些（通常稱為“抗體-定向成像”）。本領域已知許多合適的成像劑，以及將它們與抗體連接的方法（參見，例如，美國專利5,021,236、4,938,948和4,472,509）。使用的成像部分可以是順磁離子、放射性同位素、螢光染料、NMR可檢測物質和X射線成像劑。　　在順磁離子的情況下，可涉及如下示例離子：鉻（III）、錳（II）、鐵（III）、鐵（II）、鈷（II）、鎳（II）、銅（II）、釹（III）、釤（III）、鐿（III）、釓（III）、釩（II）、鋱（III）、鏑（III）、鈥（III）和/或鉺（III），其中特別優選釓。在其他環境中有用的離子（比如，X射線成像）包括但不限於鑭（III）、金（III）、鉛（II），尤其是鉍（III）。　　在用於治療和/或診斷應用的放射性同位素的情況下，可涉及²¹¹ 砹、¹⁴ 碳、⁵¹ 鉻、³⁶ 氯、⁵⁷ 鈷、⁵⁸ 鈷、銅⁶⁷ 、¹⁵² Eu、鎵⁶⁷ 、³ 氫、碘¹²³ 、碘¹²⁵ 、碘¹³¹ 、銦¹¹¹ 、⁵⁹ 鐵、³² 磷、¹⁸⁶ 錸、¹⁸⁸ 錸、⁷⁵ 硒、³⁵ 硫、^99m 鍀和/或⁹⁰ 釔。在某些實施方式中，¹²⁵ I通常是優選使用的，且^99m m鍀和/或¹¹¹ 銦也是優選的，因為它們的能量低並且適用于長程檢測。可根據本領域熟知的方法來生產本發明中放射性標記的單克隆抗體。例如，單克隆抗體可通過與碘化鈉和/或碘化鉀以及化學氧化劑（比如，次氯酸鈉）或酶氧化劑（比如，乳過氧化物酶）接觸來進行碘化。根據本發明所述的單克隆抗體可通過配體交換方法用鍀^99m 來標記，例如，通過用亞錫溶液還原高鍀酸鹽、將還原的鍀螯合到葡聚糖（Sephadex）柱上並將抗體應用於該柱。或者，可使用直接標記技術，例如，通過培養高鍀酸鹽、還原劑（比如，SNCl₂ ）、緩衝溶液（比如，鄰苯二甲酸鈉鉀溶液）和抗體來完成。通常用於將作為金屬離子存在的放射性同位素與抗體結合的中間官能團是二亞乙基三胺五乙酸（DTPA）或乙二胺四乙酸（EDTA）。　　考慮用作綴合物的螢光標記包括Alexa 350、Alexa 430、AMCA、BODIPY 630/650、BODIPY 650/665、BODIPY-FL、BODIPY-R6G、BODIPY-TMR、BODIPY-TRX、級聯藍、Cy3、Cy5，6-FAM、螢光素異硫氰酸酯、HEX、6-JOE、Oregon Green 488、Oregon Green 500、Oregon Green 514、Pacific Blue、REG、Rhodamine Green、Rhodamine Red、Renographin、ROX、TAMRA、TET、Tetramethylrhodamine和/或Texas Red。　　本發明中考慮的另一類抗體綴合物是主要用於體外的抗體綴合物，其中該抗體與二級結合配體和/或與酶（酶標籤）連接，在與生色底物接觸後產生有色產物。合適的酶的實施方式包括尿素酶、鹼性磷酸酶、（辣根）氫過氧化物酶或葡萄糖氧化酶。優選的二級結合配體是生物素和抗生物素蛋白以及鏈黴抗生物素蛋白化合物。這種標記物的使用是本領域技術人員所熟知的，並描述於例如美國專利3,817,837、3,850,752、3,939,350、3,996,345、4,277,437、4,275,149和4,366,241中。　　另一種已知的分子位點特異性附著於抗體的方法包括將抗體與基於半抗原的親和標記進行反應。基本上，基於半抗原的親和標記物與抗原結合位元點中的氨基酸反應，從而破壞該位點並阻斷特異性抗原反應。然而，這可能不是有利的，因為它導致抗體綴合物喪失抗原結合。　　含有疊氮基的分子也可用于通過低強度紫外光產生的反應性氮烯中間體來與蛋白質形成共價鍵（Potter和Haley, 1983）。特別地，嘌呤核苷酸的2-和8-疊氮基類似物已被用作定點光探針來鑒定粗細胞提取物中的核苷酸結合蛋白（Owens＆Haley, 1987；Atherton等人，1985）。2-和8-疊氮基核苷酸也已用於繪製純化蛋白質的核苷酸結合結構域（Khatoon等人，1989；King等人，1989；Dholakia等人，1989），並可用作抗體結合劑。　　本領域已知幾種方法用於將抗體與其綴合物部分連接或綴合。一些連接方法涉及使用金屬螯合物，例如，使用有機螯合劑，比如，二亞乙基三胺五乙酸酐（DTPA）；乙烯三胺四乙酸；N-氯-對甲苯磺醯胺；和/或與抗體連接的四氯-3α-6α-二苯基甘氨酸-3（美國專利4,472,509和4,938,948）。單克隆抗體也可在偶聯劑（比如，戊二醛或高碘酸鹽）的存在下與酶進行反應。在這些偶聯劑存在下或通過與異硫氰酸酯反應來製備具有螢光素標記物的綴合物。在美國專利4,938,948中，使用單克隆抗體來實現乳腺腫瘤的成像，並使用接頭（比如，對羥基苯甲亞氨酸甲酯或N-琥珀醯亞胺基-3-（4-羥基苯基）丙酸酯）將可檢測的成像部分與抗體結合。　　在其他實施方式中，已考慮到，使用不改變抗體結合位點的反應條件來通過選擇性地在免疫球蛋白的Fc區中引入巰基以衍生出免疫球蛋白。已公開了根據該方法產生的抗體綴合物來顯示出改善的壽命、特異性和靈敏度（美國專利5,196,066，其通過引用併入本發明）。效應分子或報告分子的位點特異性附著（其中報導分子或效應分子與Fc區中的碳水化合物殘基綴合）也已在文獻中公開（O’Shannessy等人，1987）。據報導，該方法產生診斷和治療上有希望的抗體，目前正在進行臨床評估。使用方法 在另一個方面中，本發明還提供了一種使用本發明所述的抗體或抗原結合片段來診斷或治療IgA相關病症的方法。 A. IgA相關病症　　如本發明所用的“IgA相關疾病”是指由IgA或IgA表達細胞的表達或活性的增加或減少引起、加劇或以其他方式與其相關的任何疾病。與IgA或表達IgA的細胞相關的病症可以是免疫相關的疾病或病症、感染和癌症。在一些實施方式中，IgA相關病症是IgA腎病（IgAN）、過敏性紫癜（HSP）、乳糜瀉或癌症。　　IgA腎病（IgAN）是世界範圍內最常見的人腎小球腎炎形式，其特徵在於IgA沉積在腎小球中。雖然人IgA腎病的機制尚未完全闡明，但高血清IgA水準、增強的IgA特異性Th細胞和IgA特異性調節性T細胞數量的減少表明，患有該疾病的患者存在IgA產生的基本失調。此外，粘膜感染復發的臨床相關性、到呼吸道病原體的血清抗體滴度的升高以及這些患者的飲食成分都表明粘膜免疫也可能參與IgA腎病的發病機制。　　在一些實施方式中，IgA相關病症與IgA缺乏症有關或相關，所述IgA缺乏症是最常見的原發性免疫球蛋白缺乏症。白種人中IgA缺乏症的患病率約為500分之一，而在一些亞洲人群中則非常罕見。在健康獻血者當中，IgA缺乏症的患病率的範圍是從歐洲血統的328-633之一到中國的5000分之一和日本的18,500分之一併在印度甚至更低。　　原發性IgA缺乏症是由終末淋巴細胞分化缺陷引起的，導致血清和粘膜IgA的產生不足；受影響的個體具有正常的IgA基因。許多非免疫球蛋白基因與IgA缺乏症有關。　　許多自身免疫性疾病與原發性IgA缺乏症相關。最常見的相關現象是與乳糜瀉（CD）相關，這具有特殊意義，因為CD通常通過檢測明顯缺乏IgA缺乏症的特異性IgA抗體來進行診斷。不表現出任何自身免疫疾病的IgA缺陷症受試者的血清樣品通常含有自身抗體。據建議，具有抗食物抗體的IgA缺陷症受試者可具有增強的胃腸道抗原吸收力，且食物衍生的抗原可能與自身抗原進行交叉反應。腸道微生物抗原的分子模擬也可發揮作用。　　據報導，顯著比例的IgA缺陷症個體在其血清中具有抗IgA抗體。出於這個原因，給予IgA缺乏症個體的血液或血液製品可導致嚴重甚至致命的輸血反應，儘管這種反應很少見。（Ann. Clin. Biochem. 2007; 44:131-139）。實際上，用IgA吸收的IVIG已被用於向與IgG或特異性抗體缺乏相關的IgA缺陷症患者輸注。　　大多數IgA缺乏症個體患者不會過度易受感染，除非IgG2產生不足。當同時發生IgA和IgG亞型缺陷時，存在顯著的發病率，主要表現為復發性肺竇感染。IgA的非必需性可能反映了IgM取代IgA作為分泌物中的主要抗體的能力，且確實在患有IgA缺陷症的人的腸粘膜中發現了增加數量的產生IgM的漿細胞。因為IgM是J鏈連接的聚合物，所以在腸粘膜中產生的IgM被pIgR有效地結合並作為分泌性IgM通過上皮細胞被轉運到腸腔中。這種備用機制的重要性已在敲除性小鼠中顯示出來。單獨缺乏IgA的動物具有正常表型，但缺乏pIgR的動物對粘膜感染敏感。人類從未報導過有pIgR的遺傳缺失，這表明這種缺陷症是致命的。　　已通過胚胎幹細胞中IgA轉換區和恒定區的靶向缺失，建立了患有IgA缺陷症的鼠模型。來自IgA缺陷症小鼠的B細胞無法在體外響應於TGF-β而產生IgA。IgA缺陷症小鼠在血清和胃腸分泌物中表達較高水準的IgM和IgG，並在血清和肺分泌物中表達IgE的水準降低。IgG亞類的表達是複雜的，最一致的發現是血清和分泌物中IgG2b增加而IgG3減少。在針對流感的粘膜免疫後未觀察到可檢測的IgA抗體；然而，與野生型小鼠相比，血清和分泌物中均觀察到IgM抗體水準升高。淋巴組織的發育以及T和B淋巴細胞功能似乎正常。儘管在這些生髮中心或腸固有層中沒有IgA，但IgA缺陷症小鼠中的Peyer斑塊發育良好，具有突出的生髮中心。　　來自IgA缺陷症小鼠的淋巴細胞對與野生型小鼠相當的T和B細胞有絲分裂進行應答，而來自IgA缺陷症小鼠的T細胞則產生相當水準的IFN-和IL-4 mRNA以及蛋白質。總之，具有靶向缺失IgA轉換區和恒定區的小鼠完全缺乏IgA並表現出其他Ig同種型的改變的表達，特別是IgM、IgG2b、IgG3和IgE，除此之外則具有正常的淋巴細胞發育、增殖反應和細胞因數產生（The Journal of Immunology (1999) 162:2521-2529）。　　在某些實施方式中，所述IgA相關病症是癌症。在某些實施方式中，所述癌症包括，例如，非小細胞肺癌（鱗狀/非鱗狀）、小細胞肺癌、腎細胞癌、結腸直腸癌、結腸癌、卵巢癌、乳腺癌（包括基底乳腺癌、導管癌和小葉乳腺癌）、胰腺癌、胃癌、膀胱癌、食道癌、間皮瘤、黑色素瘤、頭頸癌、甲狀腺癌、肉瘤、前列腺癌、膠質母細胞瘤、宮頸癌、胸腺癌、黑色素瘤、骨髓瘤、真菌病真菌、梅克爾細胞癌（MCC）、肝細胞癌（HCC）、纖維肉瘤、粘液肉瘤、脂肪肉瘤、軟骨肉瘤、成骨肉瘤和其他肉瘤、滑膜瘤、間皮瘤、尤因氏腫瘤、平滑肌肉瘤、橫紋肌肉瘤、淋巴惡性腫瘤、基底細胞癌、腺癌、汗腺癌、甲狀腺髓樣癌、乳頭狀甲狀腺癌、嗜鉻細胞瘤皮脂腺癌、乳頭狀癌、乳頭狀腺癌、髓樣癌、支氣管癌、肝癌、膽管癌、絨毛膜癌、腎母細胞瘤、宮頸癌、睾丸腫瘤、精原細胞瘤。在某些實施方式中，血液病包括，例如，經典霍奇金淋巴瘤（CHL）、原發性縱隔大B細胞淋巴瘤、富含T細胞/組織細胞的B細胞淋巴瘤、急性淋巴細胞白血病（ALL）、急性髓細胞白血病（AML）、急性髓細胞白血病、急性髓性白血病和成髓細胞、早幼粒細胞、髓單核細胞、單核細胞白血病和紅白血病、慢性粒細胞（粒細胞）白血病、慢性粒細胞白血病、慢性淋巴細胞白血病、真性紅細胞增多症、肥大細胞源性腫瘤、EBV陽性和陰性PTLD、彌漫性大B細胞淋巴瘤（DLBCL）、漿樣性淋巴瘤、結外NK/T細胞淋巴瘤、鼻咽癌、HHV8相關的原發性積液淋巴瘤、非霍奇金淋巴瘤、多發性骨髓瘤、瓦爾登斯特倫的巨球蛋白血症、重鏈疾病、骨髓增生異常綜合征、毛細胞白血病和骨髓增生異常、中樞神經系統腫瘤（CNS）（比如，原發性中樞神經系統淋巴瘤、脊髓軸腫瘤、腦幹膠質瘤、星形細胞瘤、成神經管細胞瘤、顱咽管瘤、室管膜瘤、松果體瘤、血管母細胞瘤、聽神經瘤、少突神經膠質瘤、血管瘤、黑色素瘤、神經母細胞瘤和視網膜母細胞瘤等）。 B. 抗體的施用　　在一些實施方式中，本發明提供了一種用於治療受試者中免疫球蛋白-A（IgA）相關疾病的方法，所述方法包括向受試者施用治療有效量的特異性結合於膜結合IgA的抗體或其抗原結合片段，從而在所述受試者中消除或減少表達IgA的細胞或阻斷表達IgA的B細胞的活化或免疫抑制功能。　　治療性抗體通過幾種機制起作用。除了阻斷配體與免疫細胞中的抑制劑受體結合，比如，阻斷PD-1，PD-L1和CTLA-4的抗體，還有一些是通過從迴圈或病變組織中去除蛋白質或通過阻止配體與免疫細胞上存在的活化或粘附受體結合來起作用。這些的實施方式包括抗TNF（Humira等）、抗IgE（Xolair）、抗VEGF（Avastin等）、抗IL17A（Cosentyx）、抗IL5（NUCALA、CINQAIR）、抗IL-6（Sylvant）、抗IL6受體（Actemra）和抗整聯蛋白（Tysabri、Entyvio等）等。　　治療性抗體還通過ADCC、CDC、吞噬作用、細胞凋亡、壞死或壞死性凋亡而引發致病類型細胞的消耗來起作用。例如，已顯示抗CD20（Rituxan、Gazyva、Ocrevus）抗體降低B細胞。　　本發明提供的抗體或其抗原結合片段的治療有效量（當單獨使用或與其他藥劑如化學治療劑組合使用時）取決於本領域已知的各種因素，比如，待治療的疾病類型、抗體的類型、體重、年齡、既往病史、現有藥物、受試者的健康狀況、免疫狀況和交叉反應、過敏的可能性、敏感性和不良副作用，以及施用途徑和疾病的類型、嚴重程度和發展以及主治醫師或獸醫的自由裁量權。在某些實施方式中，本發明提供的抗體或抗原結合片段可每日一次或多次施用約0.001mg/kg到約100mg/kg的治療有效劑量（例如，每日一次或多次施用約0.001mg/kg、約0.3mg/kg、約0.5mg/kg、約1mg/kg、約3mg/kg、約5mg/kg、約10mg/kg、約15mg/kg、約20mg/kg、約25mg/kg、約30mg/kg、約35mg/kg、約40mg/kg、約45mg/kg、約50mg/kg、約55mg/kg、約60mg/kg、約65mg/kg、約70mg/kg、約75mg/kg、約80mg/kg、約85mg/kg、約90mg/kg、約95mg/kg或約100mg/kg）。在某些實施方式中，所述抗體或抗原結合片段以約50mg/kg或更低的劑量來施用，且在某些實施方式中，劑量為20mg/kg或更低、10mg/kg或更低、3mg/kg或更低、1mg/kg或更低、0.3mg/kg或更低、0.1mg/kg或更低、或0.01mg/kg或更低、或0.001mg/kg或更低。在某些實施方式中，施用劑量可在治療過程中改變。例如，在某些實施方式中，初始施用劑量可高於隨後的施用劑量。在某些實施方式中，施用劑量可根據受試者的反應來隨治療過程進行而變化。　　可調整劑量方案以提供最佳的所需反應（例如，治療反應）。在某些實施方式中，本發明提供的抗體或抗原結合片段一次或在一系列治療中施用於受試者。在某些實施方式中，本發明提供的抗體或抗原結合片段通過一次或多次單獨施用或通過連續輸注施用於受試者，這取決於疾病的類型和嚴重程度。例如，可在美國專利4,657,760、5,206,344、5,225,212找到相關指導。　　本發明提供的抗體和抗原結合片段可通過本領域已知的任何途徑來施用，比如，腸胃外（例如，皮下、腹膜內、靜脈內（包括靜脈內輸注、肌肉內或皮內注射））或非腸胃外（例如，口服、鼻內、眼內、舌下、直腸或局部）途徑。　　在某些實施方式中，本發明提供的抗體和抗原結合片段可以控釋方式來施用。可將控釋腸胃外製劑製備作為植入物、油性注射劑或微粒體系（例如，微球、微粒、微膠囊、納米膠囊、納米球和納米顆粒）（參見，Banga, A. J., Therapeutic Peptides and Proteins:Formulation, Processing, and Delivery Systems, Technomic Publishing Company, Inc., Lancaster, Pa., (1995); Kreuter, J., Colloidal Drug Delivery Systems, J. Kreuter, ed., Marcel Dekker, Inc., New York, N.Y., pp. 219-342 (1994); Tice & Tabibi, Treatise on Controlled Drug Delivery, A. Kydonieus, ed., Marcel Dekker, Inc. New York, N.Y., pp. 315-339, (1992)）。在某些實施方式中，本發明公開的抗體和抗原結合片段可在可降解或不可降解的聚合物基質中施用（參見Langer, Accounts Chem. Res. 26:537-542, 1993）。　　在某些實施方式中，當將治療有效量的本發明提供的抗體或抗原結合片段施用於受試者時，在所述受試者中消耗至少10%（例如，至少20%、至少25%、至少30%、至少35%、至少40%、至少45%、至少50%、至少55%、至少60%、至少65%、至少70%、至少75%、至少80%、至少85%、至少90%、至少95%、至少99%）的表達IgA的B細胞。　　在某些實施方式中，本發明提供的抗體或抗原結合片段可單獨施用或與一種或多種另外的治療劑或手段組合來施用。例如，本發明提供的抗體或抗原結合片段可與第二療法或用於治療癌症的第二種治療劑組合來施用，所述第二療法如：放射療法、化學療法、靶向療法、基因療法、免疫療法、激素療法、血管生成抑制、姑息治療、癌症治療手術（例如，腫瘤切除術）或一種或多種止吐藥或用於化療引起的併發症的其他治療方法，所述第二治療劑如：另一種抗體、治療性多核苷酸、化學治療劑、抗血管生成劑、細胞因數、其他細胞毒性劑、生長抑制劑。在這些實施方式中的某些實施方式中，本發明提供的抗體或抗原結合片段可與一種或多種另外的治療劑同時施用，且在這些實施方式中的某些實施方式中，所述抗體或抗原結合片段和另外的治療劑可作為相同藥物組合物的一部分來施用。然而，與另一種治療劑“組合”施用的抗體或抗原結合片段不必與所述藥劑同時或在相同的組合物中進行施用。在另一種藥劑之前或之後施用的抗體或其抗原結合片段被認為與該藥劑“組合”施用，如本發明所用，即使抗體或抗原結合片段和第二藥劑通過不同途徑來施用。在可能的情況下，與本發明提供的抗體或抗原結合片段組合施用的其他治療劑根據附加治療劑的產品資訊表中列出的時間表或根據根據Physicians’ Desk Reference 2003 (Physicians’ Desk Reference, 57th Ed; Medical Economics Company; ISBN: 1563634457; 57th edition (November 2002))或本領域熟知的方案來進行施用。 C. 組合療法　　還可能需要使用本發明的抗體結合其他抗癌療法來提供組合療法。這些療法將以有效實現一種或多種疾病參數降低的組合量提供。該過程涉及同時使細胞/受試者與兩種藥劑/療法接觸（例如，使用包含兩種藥劑的單一組合物或藥理學製劑）或同時通過使細胞/受試者與兩種不同的組合物或製劑接觸，其中一種組合物包含抗體，另一種則包含另一種藥劑。　　或者，抗體可在數分鐘至數周的間隔之前或之後進行其他治療。人們通常會確保在每次遞送的時間之間不會間隔過長，這樣治療仍然能夠對細胞/受試者產生有利的組合效果。在這種情況下，考慮到可在彼此約12-24小時內、在彼此約6-12小時內或以僅約12小時的延遲時間內用兩種方式來接觸細胞。在某些情況下，可能需要延長治療時間；然而，其中在各個施用過程之間經過了幾天（2天、3天、4天、5天、6天或7天）到幾周（1、2、3、4、5、6、7或8天）的時間。　　還可想到，將需要不止一次施用抗mIgA抗體或其他療法。可採用如下各種組合，其中抗體是“A”，而另一種療法是“B”，如下所示：也考慮其他組合。為了殺死細胞、抑制細胞生長、抑制轉移、抑制血管生成或以其他方式逆轉或減少腫瘤細胞的惡性表型，使用本發明的方法和組合物可用抗體和至少一種其他療法來接觸靶細胞或位點。這些療法將以有效殺死或抑制癌細胞增殖的組合量來提供。該過程可涉及同時使細胞/部位/受試者與藥劑/療法接觸的過程。　　在某些實施方式中，用於組合療法的藥劑選自白細胞介素-2、氯法拉濱、法呢基轉移酶抑制劑、地西他濱、鉑絡合物衍生物、奧沙利鉑、激酶抑制劑、酪氨酸激酶抑制劑、PI3激酶抑制劑、BTK抑制劑、依魯替尼、PD-1抗體、PD-L1抗體、CTLA-4抗體、LAG3抗體、ICOS抗體、TIGIT抗體、TIM3抗體、與腫瘤抗原結合的抗體、與T細胞表面標記物結合的抗體、與髓樣細胞或NK細胞表面標記物結合的抗體、烷化劑、亞硝基脲劑、抗代謝物、抗腫瘤抗生素、源自植物的生物鹼、拓撲異構酶抑制劑、激素治療藥、激素拮抗劑、芳香酶抑制劑和P-糖蛋白抑制劑。 D. 免疫檢測方法　　在某些實施方式中，本發明提供了用於預防、檢測或診斷具有免疫抑制微環境的癌症的免疫檢測方法，所述方法包括將本發明提供的抗體或抗原結合片段與生物樣品接觸並確定所述生物樣品中IgA或表達IgA的細胞的水準，所述生物樣品來自疑似患有或患有或具有患癌風險的受試者。　　一些免疫檢測方法包括酶聯免疫吸附測定（ELISA）、放射免疫測定（RIA）、免疫放射測定、螢光免疫測定、化學發光測定、生物發光測定和蛋白質印跡等。特別地，還提供了用於檢測和定量mIgA的競爭性測定法。各種有用的免疫檢測方法的步驟已在科學文獻中描述，比如，例如，Doolittle and Ben-Zeev (1999), Gulbis and Galand (1993), De Jager等人(1993)和Nakamura等人(1987)。通常，免疫結合方法包括：獲得疑似含有mIgA相關癌症的樣品，以及在允許形成免疫複合物的有效條件下（視情況而定）將所述樣品與根據本發明所述的第一抗體接觸。　　這些方法包括檢測或純化來自樣品的表達mIgA的細胞的方法。優選地，將抗體與固體載體連接（比如，以柱基質的形式），並將疑似含有表達mIgA的細胞的樣品應用於固定抗體。將不需要的組分從柱中洗掉，使表達mIgA的細胞免疫複合到固定的抗體上，然後通過從柱中除去生物體或抗原來收集固定的抗體。　　免疫結合方法還包括用於檢測和定量樣品中表達mIgA的細胞或相關組分的數量的方法，以及對結合過程中形成的任何免疫複合物進行檢測和定量。此處，將獲得疑似含有表達mIgA的細胞的樣品，並使該樣品與結合mIgA的抗體接觸，然後檢測和定量在特定條件下形成的免疫複合物的量。就抗原檢測而言，分析的生物樣品可以是疑似含有mIgA表達的任何樣品，比如，組織切片或樣品、均質化組織提取物、生物液體（包括血液和血清）或分泌物（糞便或尿液）。　　在有效條件下將所選生物樣品與抗體接觸並持續一段時間到足以允許形成免疫複合物（初級免疫複合物），這通常是將抗體組合物簡單地添加到樣品中並將混合物培育一段時間的問題，該一段時間足夠長到使抗體可形成免疫複合物，即，使抗體與mIgA結合。在此之後，通常將樣品-抗體組合物（比如，組織切片、ELISA板、斑點印跡或蛋白質印跡）洗滌以除去任何非特異性結合的抗體種類，從而僅允許檢測特異性結合在初級免疫複合物內的那些抗體。　　通常，對免疫複合物形成的檢測在本領域中是公知的，並可通過應用多種方法來實現。這些方法通常基於對標記或標記物的檢測，比如，任何放射性、螢光、生物和酶標記物。關於此類標記的使用的專利包括美國專利3,817,837、3,850,752、3,939,350、3,996,345、4,277,437、4,275,149和4,366,241。當然，通過使用本領域已知的二級結合配體（比如，第二抗體和/或生物素/抗生物素蛋白配體的結合佈置），可發現其它優點。　　檢測中使用的抗體本身可與可檢測標記連接，其中可簡單地檢測該標記，從而允許確定組合物中初級免疫複合物的量。或者，可通過對第一抗體具有結合親和力的第二結合配體來檢測初級免疫複合物內結合的第一抗體。在這些情況下，第二結合配體可與可檢測標記連接。第二結合配體本身通常是抗體，因此可稱為“二級”抗體。在有效條件下將初級免疫複合物與標記的二級結合配體或抗體接觸一段時間到足以允許形成二級免疫複合物。然後通常將第二免疫複合物洗滌以除去任何非特異性結合的標記的第二抗體或配體，然後檢測第二免疫複合物中的剩餘標記。　　其他方法包括通過兩步法檢測初級免疫複合物。如上所述，第二結合配體（比如，抗體具有結合親和力的抗體）用於形成二級免疫複合物。洗滌之後，再次在有效條件下將第二免疫複合物同具有與第二抗體結合親和力的第三結合配體或抗體接觸一段時間到足以允許形成免疫複合物（三級免疫複合物）。第三配體或抗體與可檢測標記連接，從而允許檢測由此形成的三級免疫複合物。如果需要，該系統可提供信號放大。　　一種免疫檢測方法使用兩種不同的抗體。使用第一種生物素化抗體來檢測靶抗原，然後使用第二種抗體來檢測與複合生物素連接的生物素。在該方法中，首先將待測樣品在含有第一步抗體的溶液中溫育。如果存在靶抗原，則一些抗體與抗原結合以形成生物素化的抗體/抗原複合物。然後通過相繼在鏈黴抗生物素蛋白（或抗生物素蛋白）、生物素化的DNA和/或互補的生物素化的DNA的溶液中溫育來擴增抗體/抗原複合物，其中每個步驟都向抗體/抗原複合物中添加額外的生物素位點。重複擴增步驟直至達到合適的擴增水準，此時將樣品在含有針對生物素的第二步抗體的溶液中溫育。將該第二步抗體標記，例如，使用可通過組蛋白酶學使用色原底物來檢測抗體/抗原複合物的存在的酶。通過合適的擴增，可產生宏觀可見的綴合物。　　另一種已知的免疫檢測方法利用了免疫PCR（聚合酶鏈式反應）方法。該PCR方法類似於Cantor方法直至與生物素化DNA一起溫育，但該方法不是使用多輪鏈黴抗生物素蛋白和生物素化DNA溫育，而用釋放抗體的低pH或高鹽緩衝液洗去DNA/生物素/鏈黴抗生物素蛋白/抗體複合物。然後使用得到的洗滌溶液來用合適的對照與合適的引物進行PCR反應。至少在理論上，PCR的巨大擴增能力和特異性可用於檢測單個抗原分子。　　本發明的抗體還可與通過免疫組織化學（IHC）製備的新鮮冷凍和/或福馬林固定的石蠟包埋的組織塊組合使用。從顆粒樣本來製備組織塊的方法已經成功地用於先前的各種預後因素的IHC研究中，並是本領域技術人員所熟知的（Brown等人，1990；Abbondanzo等人，1990；Allred等人，1990）。　　在又一些其他實施方式中，本發明涉及用於上述免疫檢測方法的免疫檢測試劑盒。由於抗體可用於檢測表達mIgA的細胞，因此抗體可包含在試劑盒中。因此，免疫檢測試劑盒在合適的容器裝置中包含與mIgA結合的第一抗體，和可選地包含免疫檢測試劑。　　在某些實施方式中，抗體可預先結合到固體載體上，比如，柱基質和/或微量滴定板的孔。試劑盒的免疫檢測試劑可採用多種形式中的任何一種，這些形式包括與給定抗體相關或連接的那些可檢測標記形式。還考慮到與二級結合配體相關或連接的可檢測標記。示例性的第二配體是那些具有與第一抗體結合親和力的第二抗體。　　用於本發明試劑盒的其他合適的免疫檢測試劑包括雙組分試劑，所述雙組分試劑包含具有與第一抗體結合親和力的第二抗體，以及具有與第二抗體結合親和力的第三抗體，其中所述第三抗體與可檢測標記連接。如上所述，許多示例性標記在本領域中是已知的，且所有這些標記都可與本發明結合使用。　　試劑盒還可包含適當分裝的表達mIgA的細胞的組合物（無論是標記的還是未標記的），該組合物可用於製備用於檢測測定的標準曲線。試劑盒可含有完全綴合形式、中間體形式或作為待由試劑盒使用者綴合的單獨部分的抗體-標記綴合物。試劑盒的組分可以水性介質或凍幹形式進行包裝。　　試劑盒的容器裝置通常包括至少一個小瓶、試管、燒瓶、瓶子、注射器或其他容器裝置，其中可放入抗體，或者優選可適當地進行分裝。本發明的試劑盒通常還將包括用於容納抗體、抗原和任何其他用於商業銷售的封閉的試劑容器。這種容器可包括注射或吹塑塑膠容器，其中保留有所需的小瓶。實施例 提供以下實施例是為了更好地說明要求保護的發明，而不應解釋為限制本發明的範圍。以下描述的所有具體組合物、材料和方法全部或部分地落入本發明的範圍內。這些具體的組合物、材料和方法不是為了限制本發明，而僅僅是為了說明落入本發明範圍內的具體實施方式。本領域技術人員可在不脫離本發明的範圍的情況下開發出等同的組合物、材料和方法，而無需實施本發明的能力。應當理解，可在本發明所述的程式中進行許多變化，同時仍然保持在本發明的範圍內。發明人的意圖是這些變化包括在本發明的範圍內。實施例1：構建和表達用於免疫和血清/雜交瘤篩查的重組小鼠mIgA胞外膜-近端結構域（EMPD）融合蛋白　　為了製備用於免疫敲除IgA的小鼠（IgA^- /^- ，Harriman等人），兔子或其他免疫適格動物的小鼠mIgA EMPD融合蛋白（SEQ ID NO：3），在在小鼠CH2-CH3-小鼠mIgA EMPD的N末端加入10倍his標記，並在C末端融合亮氨酸拉鍊（圖2）。然後將表達盒（SEQ ID NO：3）克隆到GenScript的專有Lenti-puro哺乳動物表達載體（GenScript, Piscataway, NJ）中。靶基因的表達由CMV啟動子驅動。首先在HEK 293T細胞中擴增慢病毒（Lentivirus）構建體，並通過超速離心慢病毒感染的293T細胞培養物的上清液來純化病毒顆粒。然後將攜帶表達盒（SEQ ID NO：3）的慢病毒用於感染CHO K1細胞以產生穩定的細胞庫。在嘌呤黴素下選擇後，將穩定的庫擴增至所需體積，並根據GenScript的補料分批方案進行培養，以表達小鼠CH2-CH3-小鼠mIgA EMPD融合蛋白。收穫後，通過過濾來澄清上清液，然後上樣到Nickle-NTA柱上進行純化。將純化的蛋白質合併並脫鹽至pH7.2的PBS中。　　為了製備小鼠mIgA EMPD融合蛋白（SEQ ID NO：4）來用於免疫小鼠血清的ELISA篩選，將上述小鼠mIgA EMPD融合蛋白的小鼠CH2-CH3序列（SEQ ID NO：3）替換為人CH2-CH3序列（圖3），並如上所述進行表達和純化用於SEQ ID NO：3構建體。實施例2：構建和表達用於免疫和血清/雜交瘤篩查的重組人mIgA胞外膜-近端結構域（EMPD）融合蛋白　　為了製備用於免疫小鼠（野生型或敲除IgA的小鼠，IgA^- /^- ）或兔子或其他免疫適格動物的人mIgA EMPD融合蛋白（SEQ ID NO：5），在小鼠CH2-CH3-人mIgA EMPD長456S的N-末端添加10xhis-標籤，並在C-末端融合亮氨酸拉鍊（圖4），以及如上所述進行表達和純化用於SEQ ID NO：3構建體。　　為了製備人mIgA EMPD融合蛋白（SEQ ID NO：6）來用於免疫小鼠血清的ELISA篩選，將上述人mIgA EMPD融合蛋白的小鼠CH2-CH3序列（SEQ ID NO：5）替換為人CH2-CH3序列，將人mIgA EMPD長456S替換為人mIgA EMPD短序列（圖5），並如上所述進行表達和純化用於SEQ ID NO：3構建體。實施例3：在細胞表面構建和表達膜錨定小鼠/人mIgA胞外膜-近端結構域（EMPD）用於FACS結合分析和功效評估　　為了製備在細胞表面上表達的人IgA CH2-CH3小鼠mIgA EMPD融合蛋白（SEQ ID NO：7）來用於FACS結合測定，在人IgA CH2-CH3的N末端加入flag標籤，並在C末端融合來自小鼠膜IgA的胞質結構域（CytoD）和跨膜結構域（TMD），以產生人IgA CH2-CH3-小鼠mIgA EMPD（圖6）。　　為了製備在細胞表面上表達的Flag-人IgA CH2-CH3-mα1S EMPD融合蛋白（SEQ ID NO：8）來用於FACS結合測定，將如圖6所示來自小鼠膜IgA的小鼠mIgA EMPD、TMD和CytoD（SEQ ID NO：7）替換為人IgA mα1S EMPD、TMD和CytoD（圖7）。　　為了製備在細胞表面上表達的Flag-人IgA CH2-CH3-mα1L 456S EMPD融合蛋白（SEQ ID NO：9）來用於FACS結合測定，將如圖7所示的人IgA mα1S EMPD、TMD和CytoD（SEQ ID NO：8）替換為人IgA mα1L 456S EMPD、TMD和CytoD（圖8）。　　將編碼這些融合蛋白的基因克隆到pCDNA3.1表達載體（Thermo Fisher Scientific, Waltham, MA）中，並轉染到HEK293或CHO細胞中，用於表達跨膜（或膜錨定）融合蛋白，從而用於基於FACS的結合或篩選測定。實施例4：抗小鼠mIgA特異性滴度的免疫和血清篩選　　用完全弗氏佐劑並用100μg/小鼠的小鼠mIgA EMPD融合蛋白（SEQ ID NO：3）免疫每只敲除IgA的小鼠（IgA^- /^- ），然後進行下表所示的免疫接種計畫。為了從免疫的小鼠血清中篩選抗小鼠mIgA特異性滴度，使用1x包被緩衝液（Biolegend目錄號421701）中的1ug/mL的抗原將100μL/孔的96孔ELISA板（Thermo Scientific Cat＃439454）在4℃下包被過夜。每孔用200μL 1x洗滌緩衝液（Biolegend Cat＃421601）將板洗滌3次。在室溫下將200μL ELISA阻斷緩衝液[PBS+0.5%BSA（Cat＃001-000-162, Jackson Immuno Research）+0.05%聚山梨醇酯20]加入板中1小時。然後將板用每孔200uL洗滌緩衝液洗滌3次。將小鼠血清用PBS稀釋100倍作為最高濃度，然後從最高濃度以1：3連續稀釋10個點（一式三份）。用PBS將未免疫小鼠血清樣品稀釋100倍，從最高濃度以1：3連續稀釋10個點，用作陰性對照。然後以每孔100μL加入連續稀釋的未免疫和免疫的小鼠血清，並在室溫下溫育1小時。將板洗滌6次。將以1：10000稀釋的100uL HRP-F(ab’)₂ 山羊抗小鼠IgG（H+L）（Jackson ImmunoResearch Cat＃115-036-062）加入到板中並在室溫下溫育30分鐘。將板洗滌6次。將100μL TMB單組分基質（SurModics Cat＃TMBW）加入到板中，並通過加入100μL液體終止溶液（SurModics Cat＃LBSP）來終止反應。讀取650 nm的OD。　　來自＃3和＃5小鼠的血清顯示出與人IgA CH2-CH3-小鼠mIgA EMPD-亮氨酸拉鍊（SEQ ID NO：4）的陽性結合（圖9）。實施例5：小鼠雜交瘤融合和篩選　　使用來自mIgA血清陽性小鼠（＃3和＃5小鼠）的細胞來進行用mIgA免疫的小鼠的雜交瘤融合。還從這些動物收集末期采血和血清。使用人IgA CH2-CH3-小鼠mIgA亮氨酸拉鍊蛋白（SEQ ID NO：4，圖3）來進行ELISA滴度分析。ELISA結果顯示＃5小鼠的滴度略高於＃3小鼠，大約為1：10,000。從這些小鼠中回收較少量的淋巴細胞，回收量為30-75百萬個細胞/小鼠。脾臟和淋巴結比其他典型的免疫小鼠小得多。所有淋巴細胞都用於融合過程。　　培養總共22個96孔板（一個T75塊）培養物並監測抗小鼠mIgA抗體的分泌。實施例6：鑒定特異性結合小鼠mIgA的抗體　　為了在HEK293細胞上暫態表達N末端Flag標記的人IgA CH2-CH3-小鼠mIgA EMPD-TM融合蛋白（SEQ ID NO：7），將編碼融合蛋白的核酸克隆到pAC205載體（Genscript, Piscataway, NJ）中並轉染到HEK293細胞中。轉染四十八小時後，收穫轉染的HEK293細胞並用於FACS評估小鼠mIgA表達。　　將來自mIgA陽性＃3小鼠的血清樣品以1：200稀釋度與轉染的細胞結合（圖10），這表明這些小鼠血清確實含有能夠識別膜結合mIgA的抗體。　　為了生成表達N末端Flag標記的人IgA CH2-CH3-小鼠mIgA EMPD-TM融合蛋白（SEQ ID NO：7）的CHO穩定細胞系，將編碼融合蛋白的核酸克隆到pAC226穩定表達載體（Genscript, Piscataway, NJ）中並轉染到CHO細胞中。轉染後48小時將嘌呤黴素加入轉染的CHO細胞培養基（6μg/ml）中。　　收穫細胞，並在從嘌呤黴素選擇中恢復CHO細胞並達到90%生存力後將其用於FACS分析。使用抗Flag mAb以及mIgA陽性小鼠（＃3小鼠）血清的FACS分析得到的結果表明膜結合的mIgA在CHO細胞表面上表達（圖11）。實施例7：免疫並鑒定特異性結合人mIgA EMPD的抗體　　用完全弗氏佐劑並用100μg/小鼠的人mIgA EMPD融合蛋白（SEQ ID NO：5）免疫野生型或敲除IgA的小鼠（IgA^- /^- ），然後進行下表所示的免疫接種計畫。在最後一次免疫後7天測試小鼠血清的人mIgA EMPD（人mIgA EMPD融合蛋白，SEQ ID NO：6）結合滴度。處死人mIgA EMPD陽性小鼠，將從脾臟和淋巴結分離的淋巴細胞用於雜交瘤融合。將融合的雜交瘤接種在96孔板中並培養。通過ELISA來篩選培養的雜交瘤上清液用於與人mIgA EMPD（SEQ ID NO：6）結合。通過FACS進一步篩選ELISA陽性孔，用於與CHO細胞膜結合的人mIgA（SEQ ID NO：8和SEQ ID NO：9）結合。將FACS陽性雜交瘤（對SEQ ID NO：8和SEQ ID NO：9均為陽性）克隆，並獲得抗體重鏈和輕鏈DNA序列。將這些陽性雜交瘤克隆重新格式化到小鼠IgA2a和人IgG1中，用於功能測試。實施例8：抗小鼠mIgA抗體對腫瘤微環境中小鼠mIgA+B細胞耗竭的體內試驗及其對調節癌症治療的作用小鼠肝癌模型　　用高脂肪飲食（MUP-uPA HFD餵養模型）餵養的主要尿蛋白-尿激酶型纖溶酶原啟動物轉基因小鼠用於測試IgA陽性免疫抑制性B細胞耗竭對肝癌進展的影響。為了建立該模型，從8周齡開始餵食MUP-uPA小鼠（Nakagawa等人，Cancer Cell (2014) 162:766-79）。MUP-uPA HFD餵養的小鼠患有伴有氣球樣變性、肝細胞死亡和細胞周圍/橋接纖維化的脂肪性肝炎，最終導致40周齡時出現自發形成的肝細胞癌（HCC）。消耗mIgA+B細胞　　在20周齡時，對基於性別（雄性）和體重隨機選擇並配對的小鼠每週注射抗小鼠mIgA抗體（1-30mg/kg）。不接受注射抗小鼠mIgA抗體的小鼠用作對照。在40周時，處死小鼠並將腫瘤體積計算為寬度² ´長度/2。對於多個自發性肝腫瘤，加入單個腫瘤的體積以獲得總腫瘤體積。結果　　在注射抗小鼠mIgA抗體的MUP-uPA HFD餵養的小鼠中產生的腫瘤體積顯著小於對照組，這表明mIgA+B細胞的消耗抑制了肝癌進展。實施例9：通過抗人mIgA抗體誘導B細胞凋亡　　Ramos-hmIgA（人mIgA）細胞用於測試抗人mIgA抗體對誘導人mIgA+B細胞裂解的影響。Ramos細胞（ATCC: Manassas, VA,＃CRL-1596）是人Burkitt淋巴瘤細胞系。通過人膜錨定的IgA（SEQ ID NO：8或9）的逆轉錄轉染來生成表達人mIgA的Ramos細胞。用細胞凋亡測定在培養基（RPMI 1640, 10%FBS, 2mM Gultamine）中培養至密度為0.2 ´10⁶ /1.5ml的Ramos-hmIgA細胞的細胞裂解。在細胞凋亡測定開始之前，通過ficoll梯度除去死細胞來降低測定中細胞死亡的背景水準。在有和沒有抗hmIgA抗體或對照抗體的溶液中將0.2 ´10⁶ 個細胞一式三份進行培養72小時。然後收穫細胞並使用膜聯蛋白V-FITC凋亡檢測試劑盒I（BD Biosciences, San Jose, CA）來分析細胞凋亡水準。將細胞在冷PBS中洗滌兩次，然後重懸於100μl 1´結合緩衝液（0.1M Hepes/NaOH（pH7.4），1.4M NaCl，25mM CaCl₂ ）中。然後在黑暗中用2.5ul膜聯蛋白V-FITC抗體和5ul碘化丙啶（PI）來染色細胞。15分鐘後，向每個試管中加入400μl 1´結合緩衝液，並在FACS機上分析細胞。每個樣本收集大約10-20,000個事件。對於膜聯蛋白-V和PI，死細胞均為陽性。使用FlowJo FAC分析軟體（Tree Star, Inc., Ashland, OR）來計算每個已死和垂死群體的百分比。一式三份的資料是計算的平均值和標準差。細胞凋亡百分比計算為已死和垂死細胞的總和，並使用Excel繪製圖表。　　抗IgM抗體（Kaptein, J.等人；JBC (1996) Vol.271, No:31, 18875-18884）用作陽性對照，用於誘導Ramos-hmIgA細胞系中的細胞凋亡。抗pg120 mIgG1抗體用作陰性對照。抗人IgA抗體也用於進行比較。　　我們的結果顯示抗gp120抗體不會在未處理的細胞上誘導細胞凋亡。抗hmIgA抗體誘導Ramos-hmIgA細胞的凋亡。實施例10：通過抗人mIgA抗體誘導ADCC 　　抗體依賴性細胞介導毒性使細胞毒性細胞能夠（通過抗體）結合抗原結合靶細胞，且隨後用細胞毒素殺死靶細胞。具有ADCC活性或增強的ADCC活性的抗mIgA抗體可在治療IgA介導的病症中具有增強的治療價值。　　已經發現在非岩藻糖基化的哺乳動物細胞中產生的抗體具有增強的ADCC活性。以下實驗描述了岩藻糖基化和非岩藻糖基化的抗hmIgA抗體的使用。　　將NK細胞從100ml全血中分離（Stem Cell Technologies）。通過抗人CD56染色來確定NK細胞的純度。在每個測定中使用＞70%純度的CD56⁺ NK細胞。將抗hmIgA抗體和HERCEPTIN®抗Her2 MAb huIgG1同種型對照進行連續滴定。將這些抗體（50μl）與在細胞表面上過表達人mIgA的Ramos細胞（細胞系生成參見實施例9）於室溫下在含有1%FBS的RPMI-1640（無酚紅）中溫育30分鐘。然後將NK細胞（50μl）以15：1的比例（150,000 NK細胞至10,000個靶標（Ramos-hmIgA））加入細胞系。測定以一式三份進行。然後將Ramos-hmIgA、抗體和NK細胞在37℃溫育4小時。培養後，旋轉96孔U底板並收穫上清液（100μl）。然後使用LDH反應測定（Roche）來測試上清液的LDH釋放。計算僅針對靶標和裂解的靶標的細胞毒性百分比。如製造商所述，將殺菌劑與LDH反應混合物以等體積進行溫育30-60分鐘。然後在490nm處讀取板。細胞毒性百分比（%）計算如下：（Exp值-僅針對靶標）/裂解的靶標-僅針對靶標）。使用Kaleidagraph來繪製資料圖，並使用最佳擬合曲線來生成ED50值。　　我們的結果顯示HERCEPTIN®huIgG1同種型對照抗體可誘導低水準的細胞毒性。抗hmIgA抗體誘導特異性細胞毒性。岩藻糖基化和非岩藻糖基化形式的抗hmIgA抗體誘導相似的最大百分比（%）的細胞毒性（約70-80%）。基於EC50，非岩藻糖基化的抗hmIgA抗體比岩藻糖基化形式更有效。實施例11：具有人EMPD結構域的轉基因小鼠　　類似於人IgA1或IgA2基因座，小鼠IgA基因座也對導致分泌的IgA或膜IgA的替代外顯子進行編碼。為了驗證人EMPD作為針對人膜IgA的抗體的潛在靶標，我們生成具有“敲入”小鼠IgA基因座中的人EMPD結構域的小鼠。該敲入允許在IgA⁺ B細胞表面上表達具有人EMPD結構域的小鼠IgA（圖12，還參見Harriman等人，J Immunol (1999) 162: 2521-29；Mcpherson等人，Mucosal Immunology (2008) 1:11-22；Wood等，EMBO Journal (1983) 2(6)）。EMPD序列在膜錨定的IgA上表達，但不在分泌的IgA上表達。　　使用對小鼠IgA基因座（P1和P4，圖12）和人EMPD序列（P2和P3，圖12）或其成對的組合（小鼠P1和人P2；人P3和小鼠P4）特異性的引物，以通過PCR對敲入人EMPD的小鼠進行基因分型。　　使用32個迴圈的以下程式[94℃4分鐘；94℃1分鐘；60℃30秒；72℃1分鐘（30個迴圈）；72℃10分鐘]來用上述引物對純化的基因組DNA進行分析。PCR產物在2%瓊脂糖0.5×TBE凝膠電泳。預期的PCR產物（或其缺乏）以及它們的長度很好地標識了在小鼠IgA基因座上靶向敲入人EMPD用於替換小鼠EMPD。　　篩選敲入人EMPD的ES細胞和最終小鼠品系並通過Southern印跡來驗證。用適當的內切核酸酶來消化過夜的10μg純化的ES細胞或小鼠尾基因組DNA。消化的DNA在0.8%瓊脂糖1×TAE凝膠電泳。然後使用變性緩衝液（1.5M NaCl；0.5M NaOH）將DNA轉移至尼龍膜（Roche）上過夜。將膜沖洗、UV交聯，然後在DIG Easy Hyb溶液（Roche）中浸泡4小時，並在46℃下進行旋轉。使用PCR DIG探針合成試劑盒、按照製造商（Roche）的指示來通過PCR產生探針。　　編碼人EMPD片段的核酸序列 GGCTCTTGCTCTGTTGCAGATTGGCAGATGCCGCCTCCCTATGTGGTGCTGGACTTGCCGCAGGAGACCCTGGAGGAGGAGACCCCCGGCGCCAAC（SEQ ID NO：10）用於Southern印跡分析。針對未標記的PCR產物來測試探針以確保增加的尺寸和良好的DIG標記。然後將印跡用煮沸的探針過夜在46℃下進行旋轉過夜。然後根據製造商的說明，用抗DIG抗體洗滌並顯色第二天印跡。將印跡暴露於膜上15-20分鐘。實施例12：抗小鼠mIgA抗體對腫瘤微環境中人mIgA⁺ B細胞耗竭的體內試驗及其對調節癌症治療的作用小鼠肝癌模型　　將人mIgA轉基因小鼠（參見實施例11）與MUP-uPA小鼠雜交以生成MUP-uPA-hmIgA小鼠，該小鼠用於測試人mIgA B細胞耗竭對肝癌進展的影響。為了建立肝癌模型，從8周齡開始將HFD餵養MUP-uPA-hmIgA小鼠。MUP-uPA-hmIgA HFD餵養的小鼠患有伴有氣球樣變性、肝細胞死亡和細胞周圍/橋接纖維化的脂肪性肝炎，最終導致40周齡時出現自發形成的肝細胞癌（HCC）。消耗mIgA+B細胞　　在20周齡時，對基於性別（雄性）和體重隨機選擇並配對的小鼠每週注射抗小鼠mIgA抗體（1-30mg/kg）。不接受抗小鼠mIgA抗體注射的小鼠用作對照。在40周時，處死小鼠並將腫瘤體積計算為寬度² ´長度/2。對於多個自發性肝腫瘤，加入單個腫瘤的體積以獲得總腫瘤體積。結果　　在注射抗小鼠mIgA抗體的MUP-uPA-hmIgA HFD餵養的小鼠中產生的腫瘤體積顯著小於對照組，這表明耗竭人mIgA⁺ B細胞抑制了肝癌進展。　　雖然已經參考特定實施方式（其中一些是優選實施方式）具體示出和描述了本發明，但是本領域技術人員應該理解，可在不脫離本發明所公開的本發明精神和範圍的情況下，在其中進行形式和細節上的各種改變。The following description of the invention is merely intended to illustrate various embodiments of the invention. Therefore, the specific modifications discussed are not to be construed as limiting the scope of the invention. It is apparent to those skilled in the art that various equivalents, changes and modifications can be made without departing from the scope of the invention, and it should be understood that these equivalent embodiments are included in the invention. All references, including publications, patents, and patent applications, are hereby incorporated by reference in their entirety hereindefinition The singular forms "a", "an", and "the" The term "about" as used herein, when referring to a measurable value such as quantity, duration, etc., is meant to include a variation of ±10% from the specified value. Unless otherwise stated, all numbers expressing quantities of ingredients, properties (e.g., molecular weight), reaction conditions, and the like, as used in the specification and claims, are understood to be modified in all instances by the term "about." Correspondingly, the numerical parameters set forth in the following description and the appended claims are approximations, which may vary depending on the desired properties to be achieved by the subject matter disclosed herein. At the very least, it is not intended to limit the application of the equivalents to the scope of the claims. Although a wide range of numerical ranges and parameters are defined as approximations for the present invention, the values recorded in the particular embodiments are as precise as possible. However, any numerical value contains certain inherent errors necessarily resulting from the standard deviation of the respective test. The term "antigen" (Ag) as used herein refers to a substance that is capable of inducing an adaptive immune response. In particular, an antigen is a substance that can serve as a target for adaptive immune response receptors. Antigens are usually proteins and polysaccharides, and lipids are relatively rare. Suitable antigens include, but are not limited to, parts of bacteria (enclosure, capsule, cell wall, flagella, pili, and toxins), viruses, and other microorganisms. Antigens also include tumor antigens, for example, antigens produced by tumor mutations. As used herein, an antigen also includes an immunogen and a hapten. The term "antibody" as used herein includes any immunoglobulin, monoclonal antibody, polyclonal antibody, multispecific antibody or bispecific (bivalent) antibody that binds to a particular antigen (or antigens). A natural intact antibody comprises two heavy chains and two light chains. Each heavy chain is made up of a variable region (V_H And the first, second and third constant regions (C_H 1,C_H 2, C_H 3) composition, and each light chain is made up of a variable region (V_L And constant region (C_L )composition. Mammalian heavy chains are classified as alpha, delta, epsilon, gamma and mu, and mammalian light chains are classified as lambda or kappa. The antibody has a "Y" shape in which the stem of Y consists of the second and third constant regions of the two heavy chains joined together by disulfide bonds. Each arm of Y comprises a variable region in a single heavy chain and a first constant region that binds to the variable and constant regions of a single light chain. The variable regions of the light and heavy chains are responsible for antigen binding and are commonly referred to as Fv (for variable fragments) or Fv fragments. The variable regions in both chains typically comprise three highly variable loops, termed complementarity determining regions (CDRs) (light (L) strand CDRs include LCDR1, LCDR2, and LCDR3, and heavy (H) strand CDRs include HCDR1, HCDR2 , HCDR3). The CDR boundaries of the antibodies and antigen-binding fragments disclosed herein can be defined or identified by the convention of Chothia, Kabat or Al-Lazikani (Chothia, C et al, J Mol Biol 186(3):651-63 (1985); Chothia , C. and Lesk, AM, J Mol Biol, 196:901 (1987); Chothia, C, et al, Nature 342 (6252): 877-83 (1989); Kabat EA et al., National Institutes of Health, Bethesda, Md. (1991); Al-Lazikani, B., Chothia, C., Lesk, AM, J Mol Biol 273(4): 927 (1997)). The three CDRs are inserted between the flanking extensions called the framework regions (FR), which are more highly conserved than the CDRs and form a scaffold that supports the hypervariable loops. The constant regions of the heavy and light chains are not involved in antigen binding, but exhibit various effector functions. Antibodies are assigned to various classes based on the amino acid sequence of their heavy chain constant regions. The five major classes or isotypes of antibodies are IgA, IgD, IgE, IgG, and IgM, characterized by the presence of alpha, delta, epsilon, gamma, and mu heavy chains, respectively. These major antibody classes can be divided into subclasses, such as IgG1 (γ1 heavy chain), IgG2 (γ2 heavy chain), IgG3 (γ3 heavy chain), IgG4 (γ4 heavy chain), IgA1 (α1 heavy chain) in humans. Or IgA2 (α2 heavy chain) and IgG1 (γ1 heavy chain), IgG2a (γ2a heavy chain), IgG2b (γ2b heavy chain) and IgG3 (γ3 heavy chain) in mice. The term "antigen-binding fragment" as used in the present invention refers to a part of a protein capable of specifically binding to an antigen. In certain embodiments, the antigen binding fragment is derived from an antibody comprising one or more CDRs, or any other antibody fragment that binds to an antigen but does not comprise the entire native antibody structure. In certain embodiments, the antigen-binding fragment is not derived from an antibody, but is derived from a receptor. Examples of antigen-binding fragments include, but are not limited to, diabody, Fab, Fab', F(ab')₂ , Fv fragment, disulfide-stabilized Fv fragment (dsFv), (dsFv)₂ , bispecific dsFv (dsFv-dsFv'), disulfide stabilized diabody (ds diabody), single chain antibody molecule (scFv), scFv dimer (divalent diabody), multispecific antibody, single Domain antibodies (sdAb), camel antibodies or Nanobodies, domain antibodies and bivalent domain antibodies. In certain embodiments, the antigen binding fragment is capable of binding to the same antigen to which the parent antibody binds. In certain embodiments, an antigen binding fragment can comprise one or more CDRs from a particular human antibody that is grafted into a framework region from one or more different human antibodies. In certain embodiments, the antigen binding fragment is derived from a receptor and contains one or more mutations. In certain embodiments, the antigen-binding fragment does not bind to a natural ligand of the receptor from which the antigen-binding fragment is derived. "Fab" with respect to an antibody refers to an antibody portion consisting of a single light chain (variable region and constant region) which binds to the variable region of the single heavy chain and the first constant region by a disulfide bond. "Fab'" refers to a Fab fragment comprising a portion of the hinge region. "F(ab')₂ "refers to a dimer of Fab'. "Fc" with respect to an antibody refers to an antibody portion consisting of a second and a third constant region of a first heavy chain, the portion being passed through a disulfide bond and a second heavy chain Binding to the third constant region. The Fc portion of the antibody is responsible for various effector functions, such as ADCC and CDC, but does not function in antigen binding. "Fc" as used herein also refers to the second and third constant regions of a single heavy chain. The wild type Fc refers to an Fc sequence which is usually found in nature without modification or mutation. The Fc region of a native antibody produced by a mammalian cell usually comprises a branched biantennary oligosaccharide, usually through N- The linker is linked to Asn297 of the CH2 domain of the Fc region. See, for example, Wright et al, TIBTECH (1997) 15:26-32. The oligosaccharide may comprise various carbohydrates (eg, mannose, N-acetylene) Glucosamine (GlcNAc), galactose and sialic acid) and fucose linked to GlcNAc in the "stem" of the biantennary oligosaccharide structure. The carbohydrate attached to the Fc region may vary. In some embodiments, For oligosaccharides in IgG Modifications to produce IgGs with certain other improved properties. For example, antibody modifications are provided that have a carbohydrate structure that lacks (directly or indirectly) fucose attached to the Fc region. Modifications of "non-fucosylation" can have improved ADCC function. See, for example, U.S. Patent Publication No. US 2003/0157108 (Presta, L.); US 2004/0093621 (Kyowa Hakko Kogyo Co., Ltd). Examples of publications related to "non-fucosylation", "defucosylation" or "fucose deficiency" antibody modification include: US 2003/0157108; WO 2000/61739; WO 2001/29246; US 2003/0115614; US 2002/0164328; US 2004/0093621; US 2004/0132140; US 2004/0110704; US 2004/0110282; US 2004/0109865; WO 2003/085119; WO 2003/084570; WO 2005/035586; WO 2005/035778; WO2005/053742; WO2002/031140; Okazaki et al. J. MoL Biol. 336:1239-1249 (2004); Yamane-Ohnuki et al. Biotech. Bioeng. 87:614 (2004). Examples of cell lines of acosylated antibodies include a lack of protein fucosyl Lee 13CHO cells (Ripka et al. Arch. Biochem. Biophys. (1986) 249: 533-545; US Patent Application Publication No. 2003/0157108 A1, Presta, L; and WO 2004/056312 A1, Adams et al, special Is Example 11), knockout cell lines, such as α-1,6-fucosyltransferase gene, FUT8, knockout CHO cells (see, for example, Yamane-Ohnuki et al, Biotech, Bioeng. (2004) 87:614; Kanda, Y. et al., Biotechnol. Bioeng., (2006) 94(4): 680-688; and WO2003/085107). "Fv" with respect to an antibody refers to the smallest fragment of an antibody that carries the entire antigen binding site. Usually, the Fv fragment consists of a single light chain (V_L Variable region composition, the single light chain (V_L Variable region and single heavy chain (V_H The variable region is combined. "Fv" as used herein also refers to a variable region of a single light chain or a single heavy chain. In certain embodiments, the Fv fragments of the invention are mutated and do not have an intact antigen binding site. As used herein, "antibody-dependent cell-mediated cytotoxicity" or ADCC refers to a cytotoxic form in which it is present in certain cytotoxic cells (eg, natural killer (NK) cells, neutrophils, and giants. The secreted Ig bound by the Fc receptor (FcR) on the phage cell enables these cytotoxic effector cells to specifically bind to the target cell carrying the antigen and subsequently kill the target cell using the cytotoxin. The antibody "arms" the cytotoxic cells and kills the target cells by this mechanism. NK cells, which are the major cells that mediate ADCC, express only FcyRIII, whereas monocytes express FcyRI, FcyRII and FcyRIII. Ravetch and Kinet,Annu. Rev. Immunol. (1991) 9: Table 3 on page 464 of 457-92 summarizes Fc expression on hematopoietic cells. In order to assess the ADCC activity of the target molecule, an in vitro ADCC assay is performed, such as the in vitro ADCC assay as described in U.S. Patent No. 5,500,362 or 5,821,337. Useful effector cells for such assays include peripheral blood mononuclear cells (PBMC) and natural killer (NK) cells. Alternatively or additionally, the ADCC activity of the target molecule can be assessed in vivo, for example, in animal models, such as, for example, Clynes et al.PNAS USA (1998) 95: Animal model disclosed in 652-656. "Complement dependent cytotoxicity" or "CDC" as used in the present invention refers to lysis of target cells in the presence of complement. Activation of the classical complement pathway is initiated by the binding of the first component of the complement system (C1q) to an antibody (suitable subclass) that binds to its cognate antigen. To assess complement initiation, a CDC assay can be performed, for example, as in Gazzano-Santoro et al.J. Immunol. Methods (1996) 202: 163. A "carrier" as used in the present invention includes a pharmaceutically acceptable carrier, excipient or stabilizer which is non-toxic to cells or mammals which are used at the dosages and concentrations employed. The pharmaceutically acceptable carrier is typically an aqueous pH buffer solution. Examples of pharmaceutically acceptable carriers include buffers such as phosphates, citrates and other organic acids; antioxidants containing ascorbic acid; low molecular weight (less than about 10 residues) polypeptides; proteins such as serum white Protein, gelatin or immunoglobulin; hydrophilic polymer, such as polyvinylpyrrolidone; amino acids such as glycine, glutamine, aspartame, arginine or lysine; monosaccharides, disaccharides and others Carbohydrates, including glucose, mannose or dextrin; chelating agents such as EDTA; sugar alcohols such as mannitol or sorbitol; salt-forming counterions, such as sodium; and/or nonionic surfactants, for example, TWEENTM, polyethylene glycol (PEG) and PLURONICSTM. An antibody that "specifically binds" or "specifically" to a particular polypeptide or epitope on a particular polypeptide is one that binds to a particular polypeptide or an epitope on a particular polypeptide without substantially binding to any other polypeptide or polypeptide epitope. For example, the EMPD of an IgA-specific antibody of the invention is specific for EMPD of IgA found on membrane-bound IgA on B cells, but the latter is absent on secreted IgA. In some embodiments, the dissociation constant (Kd) of an antibody that binds to EMPD of IgA is ≦100 nM, ≦10 nM, ≦1 nM, ≦0.1 nM, ≦0.01 nM, or ≦0.001 nM (eg, 10^-8 M or lower, for example, from 10^-8 M to 10^-13 M, for example, from 10^-9 M to 10^-13 M). Antibodies that "induced apoptosis" or "apoptosis" are passed through standard apoptosis assays (eg, annexin V binding, DNA fragmentation, cell contraction, endoplasmic reticulum expansion, cell fragmentation, and/or membrane vesicles). The formation of vesicles (called apoptotic bodies) is determined by those antibodies that induce programmed cell death. For example, the apoptotic activity of the anti-IgA antibody of the present invention can be revealed by staining a surface-bound IgA-containing cell with annexin V. "Single-chain Fv antibody" or "scFv" refers to an engineered antibody consisting of a light chain variable region and a heavy chain variable region, either directly or through a peptide linker sequence Connection (Huston Js et al, Proc Natl Acad Sci USA, 85: 5879 (1988)). "Single-chain Fv-Fc antibody" or "scFv-Fc" refers to an engineered antibody consisting of an scFv linked to the Fc region of an antibody. "Single domain antibody", "sdAb", "camel antibody", "heavy chain antibody" or "HCAb" means containing two V_H Antibodies with domains and no light chain (Riechmann L. and Muyldermans S., J, Immunol Methods 231(1-2): 25-38 (1999); Muyldermans S., J Biotechnol 74(4): 277-302 ( 2001); WO94/04678; WO94/25591; U.S. Patent No. 6,005,079). Heavy chain antibodies were originally derived from camelids (camel, dromedary and llama). Although there is no light chain, camelid antibodies have a true antigen binding pool (Hamers-Casterman C. et al, Nature 363 (6428): 446-8 (1993); Nguyen VK. et al., Immunogenetics 54(1): 39- 47 (2002); Nguyen VK. et al., Immunology 109(1): 93-101 (2003)). Variable domain of heavy chain antibody (V_H The H domain) represents the smallest known antigen binding unit produced by an adaptive immune response (Koch-Nolte F. et al., FASEB J 21(13): 3490-8. (2007)). "Nanobody" refers to a V from a heavy chain antibody or camelid antibody_H H domain and two constant domains C_H 2 and C_H 3 composed of antibody fragments. "Dual antibody" includes a small antibody fragment having two antigen binding sites, wherein the fragment comprises V in the same polypeptide chain_L Domain-connected V_H Domain (V_H -V_L Or V_L -V_H (To participate, for example, Holliger P. et al., Proc Natl Acad Sci U S A. 90(14):6444-8 (1993); EP404097; WO93/11161). By using a linker that is too short to allow pairing between the two domains on the same chain, the domain is forced to pair with the complementary domain of the other chain, resulting in two antigen binding sites. Antigen binding sites can target the same or different antigens (or epitopes). "Domain antibody" refers to an antibody fragment that contains only a heavy chain variable region or a light chain variable region. In some embodiments, two or more V_H The domain is covalently linked to a peptide linker to produce a bivalent or multivalent domain antibody. Two Vs of bivalent domain antibodies_H The domains can target the same or different antigens. In some embodiments, "(dsFv)₂ Contains three peptide chains: linked by a peptide linker and passed through a disulfide bond with two V_L Partially combined two V_H section. In certain embodiments, the "bispecific ds diabody" comprises V_H1 And V_L1 Disulfide bond between V and V_L1 -V_H2 (also connected by peptide linker) combined V_H1 -V_L2 (connected by peptide linker). In certain embodiments, "bispecific dsFv" or "dsFv-dsFv" comprises three peptide chains: V_H1 -V_H2 Part, wherein the heavy chain is linked by a peptide linker (eg, a long flexible linker) and passes through a disulfide bond and V, respectively._L1 And V_L2 Partial binding wherein each disulfide-paired heavy and light chain has a different antigen specificity. In certain embodiments, "scFv dimer" is included with another V_H -V_L Partially dimerized V_H -V_L a bivalent diabodies (linked by a peptide linker) or a bivalent ScFv (BsFv), thereby a partial V_H V with another part_L The ligands form two binding sites that can target the same antigen (or epitope) or different antigens (or epitopes). In other embodiments, the "scFv dimer" is included with V_L1 -V_H2 (also connected by peptide linker) connected V_H1 -V_L2 Bispecific diabodies (linked by peptide linkers), thus V_H1 And V_L1 Coordination, V_H2 And V_L2 Coordination, and each coordination pair has a different antigen specificity. The term "humanized" as used herein with reference to an antibody or antigen-binding fragment means that the antibody or antigen-binding fragment comprises a CDR derived from a non-human animal, a FR region derived from a human, and, when applicable, a human-derived constant Area. In certain embodiments, a humanized antibody or antigen-binding fragment can be used as a human therapeutic because it has reduced immunogenicity in humans. In some embodiments, the non-human animal is a mammal, such as a mouse, rat, rabbit, goat, sheep, guinea pig, hamster or camel. In some embodiments, the humanized antibody or antigen-binding fragment consists essentially of a fully human sequence, in addition to a non-human CDR sequence. In some embodiments, a FR region derived from a human may comprise the same amino acid sequence as an antibody derived from a human, or may comprise some amino acid changes, eg, no more than 10, 9, 8, 7, 6, 5, 4, 3, 2 or 1 amino acid change. In some embodiments, such a change in amino acid may be present only in the heavy chain FR region, only in the light chain FR region, or in both chains. In some preferred embodiments, the humanized antibody comprises human FR1-3 and human JH and JK. The term "epitope" as used in the present invention refers to a specific atom or amino acid group on an antigen to which an antibody binds. The epitope can be a linear epitope or a conformational epitope. Linear epitopes are formed from contiguous amino acid sequences from antigens and interact with antibodies based on their primary structure. In another aspect, the conformational epitope consists of a discrete portion of the antigenic amino acid sequence and interacts with the antibody based on the 3D structure of the antigen. Typically, the epitope is about five or six amino acids in length. If the two antibodies exhibit competitive binding of the antigen, they can bind to the same epitope within the antigen. The term "therapeutic antibody" or "therapeutic antibodies" refers to an antibody that is used for therapeutic purposes before or after market authorization. The term "nanoparticle" as used in the present invention refers to particles having a size between 1 and 1000 nanometers. In certain embodiments, the nanoparticles are particles having a size between 1 and 100 nanometers. A number of nanoparticles have been disclosed, including, for example, superparamagnetic iron oxide (SPIO) nanoparticles (see U.S. Patent Application No. US20100008862), metal nanoparticles (e.g., gold or silver nanoparticles (see, for example, Hiroki Hiramatsu, FEO, Chemistry of Materials 16, 2509-2511 (2004))), semiconductor nanoparticles (e.g., quantum dots having single or multiple components, such as CdSe/ZnS (see, for example, M. Bruchez et al, science 281, 2013-2016 (1998)), quantum dots doped with heavy metals (see, for example, Narayan Pradhan et al., J. Am. chem. Soc. 129, 3339-3347 (2007)) or other semiconductor quantum dots; polymer nano Granules (for example, by PLGA (poly(lactic-co-glycolic acid)) (see, for example, Minsoung Rhee et al, Adv. Mater. 23, H79-H83 (2011)), PCL (polycaprolactone) (see, For example, Marianne Labet et al., Chem. Soc. Rev. 38, 3484-3504 (2009)), PEG (polyethylene glycol) or one of the other polymers or a combination thereof; enamel nanoparticles And non-SPIO magnetic nanoparticles ( For example, MnFe2O4 (see, for example, Jae-Hyun Lee et al, Nature Medicine 13V95-99 (2006)), synthetic antiferromagnetic nanoparticles (SAF) (see, for example, A. Fu et al., Angew. Chem. Int) Ed. 48, 1620-1624 (2009)), and other types of magnetic nanoparticles. "Cells" as used in the present invention may be prokaryotic or eukaryotic. For example, prokaryotic cells include bacteria. For example, eukaryotic cells include Fungi, plant cells, and animal cells. Types of animal cells (eg, mammalian cells or human cells) include, for example, cells from the loop/immune system or organ, eg, B cells, T cells (cytotoxic T cells, Natural killer T cells, regulatory T cells, T helper cells), natural killer cells, granulocytes (eg, basophils, eosinophils, neutrophils, and excessively secreted neutrophils), single Nuclear cells or macrophages, red blood cells (eg, reticulocytes), mast cells, platelets or megakaryocytes and dendritic cells; cells from the endocrine system or organs, eg, thyroid gland Cells (eg, thyroid epithelial cells, parafollicular cells), parathyroid cells (eg, parathyroid primary cells, eosinophils), adrenal cells (eg, chromaffin cells), and pineal cells (eg, Pineal cells; cells from the nervous system or organs, for example, glioblasts (eg, astrocytes and oligodendrocytes), microglia, large cell neurosecretory cells, stellate cells, and Bucher cells And pituitary cells (eg, gonadotropins, corticosteroids, thyroxine, growth hormone, and milk vegetative cells); cells from the respiratory system or organs, eg, lung cells (type I lung cells and type II lung cells), Clara Cells, goblet cells, and alveolar macrophages; cells from the circulatory system or organs (eg, cardiomyocytes and pericytes); cells from the digestive system or organs, eg, gastric primary cells, parietal cells, goblet cells, cells Cells, G cells, D cells, ECL cells, I cells, K cells, S cells, enteroendocrine cells, intestinal chromaffin cells, APUD cells, and hepatocytes (for example, Cells and Kupffer cells; cells from the dermal system or organ, for example, bone cells (eg, osteoblasts, bone cells, and osteoclasts), dental cells (eg, cementoblasts and ameloblasts), Chondrocytes (eg, chondrocytes), skin/hair cells (eg, hair cells, keratinocytes and melanocytes (痣 cells), muscle cells (eg, muscle cells), adipocytes, fibroblasts, and tendon cells; Cells from the urinary system or organs (eg, podocytes, juxtaglomerular cells, intraglomerular mesangial cells, extraglomerular mesangial cells, proximal renal tubule brush border cells, and macular density) Cells); and cells from the reproductive system or organs (eg, sperm, support cells, interstitial cells, eggs, oocytes). The cells can be normal, healthy cells; or diseased or unhealthy cells (eg, cancer cells). The cells also include mammalian fertilized eggs or stem cells, including embryonic stem cells, fetal stem cells, induced pluripotent stem cells, and adult stem cells. Stem cells are cells that are capable of undergoing cell division loops while remaining undifferentiated and differentiated into specialized cell types. The stem cells may be pluripotent stem cells, pluripotent stem cells, oligopotent stem cells, and pluripotent stem cells, any of which may be induced from somatic cells. Stem cells can also include cancer stem cells. Mammalian cells can be rodent cells such as mouse, rat, hamster cells. The mammalian cell can be a rabbit-shaped cell, for example, a rabbit cell. The mammalian cell can also be a primate cell, for example, a human cell. "IgA-associated disease" as used in the present invention refers to any disease caused, aggravated or otherwise associated with an increase or decrease in expression or activity of an IgA or IgA-expressing cell. These may include IgA nephropathy (IgAN), Henoch-Schonlein purpura (HSP), celiac disease, and cancer. The term "pharmaceutically acceptable" means that the specified carrier, vehicle, diluent, excipient, and/or salt is generally chemically and/or physically compatible with, and physiologically compatible with, other ingredients comprising the formulation. Body compatible. The term "subject" as used in the present invention refers to a human or any non-human animal (eg, mouse, rat, rabbit, dog, cat, cow, pig, sheep, horse or primate). Humans include prenatal and postnatal forms. In many embodiments, the subject is a human. A subject can be a patient, referring to a person presented to a medical provider to diagnose or treat the disease. The term "subject" as used in the present invention may be interchanged with "individual" or "patient." The subject may or may be susceptible to the disease or condition, but may or may not exhibit symptoms of the disease or condition. The term "therapeutically effective amount" or "effective amount" as used herein, refers to a dose or concentration of a drug effective to treat a disease or condition associated with IgA or IgA expressing cells. For example, with respect to the use of an antibody or antigen-binding fragment disclosed herein for the treatment of cancer, a therapeutically effective amount is a dose or concentration of an antibody or antigen-binding fragment that is capable of achieving a reduction in tumor volume, eradication of all or part of a tumor, inhibition or Slows tumor growth or infiltration of cancer cells into other organs, inhibits the growth or proliferation of cells that mediate cancer states, inhibits or slows the metastasis of tumor cells, improves any symptoms or markers associated with tumors or cancer, prevents or delays tumors or cancer Development, or some combination thereof. "Trating, treatment" conditions for use in the present invention include preventing or ameliorating a condition, slowing the onset or rate of development of the condition, reducing the risk of developing the condition, preventing or delaying the development of symptoms associated with the condition, reducing or ending the condition associated with the condition. Symptoms, complete or partial regression of the condition, cure of the condition, or some combination thereof.IgA And produce IgA Cell Immunoglobulins (Igs) are expressed as secreted proteins or membrane-bound proteins, depending on the stage of differentiation of B cells. On the surface of B lymphocytes, membrane-bound Igs constitute the antigen-specific component of the B cell receptor (BCR). Conversely, when produced by differentiated plasma cells, Igs actively secrete and become a relevant component of serum. Immunoglobulins belong to the immunoglobulin superfamily (IgSF). They consist of two heavy chains (H) and two light chains (L), wherein the L chain can consist of a kappa chain or a lambda chain. Each component strand contains an NH2-terminal "variable" (V) IgSF domain and one or more COOH-terminal "constant" (C) IgSF domains. Each V or C domain consists of approximately 110-130 amino acids with an average of 12,000-13,000 Da. The two Ig L chains contain only one C domain, while the Ig H chain contains three or four such domains. An H chain having three C domains tends to include a spacer hinge region between the first (CH 1) and second (CH 2) domains. Among all isoforms, CH1 is associated with the C region of the light chain. The CH2 and CH3 domains of IgG and IgA together with the CH2, CH3 and CH4 domains of IgM and IgE constitute a so-called Fc fragment which is common to both the membrane form and the secretory form. However, membrane Igs contains three additional C-terminal domains, the outer membrane proximal domain (EMPD), the transmembrane domain (TMD), and the cytoplasmic domain (CytoD). These three C-terminal domains are collectively referred to as membrane-anchored peptide segments. Membrane Igs are also known as membrane-bound Igs, membrane-anchored Igs, membrane-expressing Igs, or cell surface Igs. The Ig heavy and light chains are each encoded by a separate multigene family, and the V and C domains are each encoded by separate elements: the V(D)J gene segment encodes the V domain and the in vitro exon encodes the C domain. . The primary sequence of the V domain is functionally divided into three hypervariable intervals, called complementarity determining regions (CDRs), which are located between four stable sequence regions called frameworks (FR). Located downstream of the VDJ locus is the functional CH gene. These constant genes are composed of a series of exons, each encoding a separate domain, hinge or terminus. All CH genes can be alternatively spliced to produce two different types of carboxy termini: the end of the membrane that anchors the immunoglobulin on the surface of the B lymphocyte or the secretory end that occurs in the soluble form of immunoglobulin. In the early development of B cells, the efficiently rearranged variable domains (VH and VL) are conjugated to the μ heavy chain to produce IgM, which is then selectively spliced to produce IgD. In the late development phase, these variable domains can be conjugated to other isoforms (IgG, IgA, and IgE) in a controlled process in response to antigen stimulation and cytokine regulation. The CH gene of each isoform is arranged in the same transcriptional direction on human chromosome 14. Through the recombination between the Cμ switch (S) region and one of the other H chain constant regions (referred to as the process of class switching or class switching recombination [CSR]), the same VDJ heavy chain variable domain can be used with any H chains are juxtaposed to produce a variety of Ig isoforms. This allows B cells to customize the receptor and effector ends of antibody molecules to meet specific needs. Isotypes differ in many properties, including size, complement binding, FcR binding, and isotype response to antigen. The choice of isotype depends on the antigen itself and the signaling pathway that is activated and the local microenvironment. As a major class of antibodies found in most mammalian mucosal secretions, IgA represents the first line of defense against pathogen invasion from inhaled and ingested mucosal surfaces. Secretory IgA (S-IgA) in mucosal secretions binds to antigens (Ags), thereby limiting their absorption, inhibiting bacterial attachment to mucosal surfaces, and neutralizing various viruses that may otherwise enter the body through the mucosal surface. Since IgA is unable to efficiently activate complement, a potential host destructive inflammatory response does not occur. Significant concentrations of IgA have also been found in the serum of many species, which act as a second line of defense, mediating the elimination of pathogens that have destroyed the mucosal surface. IgA in serum binds and neutralizes Ags (eg, Ags present on microorganisms) and can help neutralize autoantigens or clear small amounts of food Ags that enter the body. Neutralization of autoantigens or exogenous Ags prevents an inappropriate immune response to these Ags. The incidence of autoimmune disease is increasing in subjects with IgA deficiency, and this finding supports the latter hypothesis. Although IgA in serum is usually a monomer, IgA in the mucosa (called secretory IgA (S-IgA)) is a dimer associated with the J chain and another polypeptide chain (secretory component) (sometimes Trimers and tetramers). Similar to IgM, the CH3 domain of IgA has a short chain tail, the J chain binds to the short strand through a disulfide bond, and the secretory component binds to one of the CH2 domains of the dimer through a disulfide bond. This polymeric form of IgA specifically binds to the polymeric immunoglobulin receptor (pIgR) and is transported through the cytoplasm of epithelial cells to the intestinal lumen or other mucosal surface. IgM also binds to pIgR and can be secreted into the gut by the same mechanism. IgA is quantitatively the major Ig isoform produced in vivo. It is estimated that 70-80% of all Ig producing cells are located in the intestinal mucosa. Thus, IgA is by far the most abundant immunoglobulin in the body, most of which is present in mucosal secretions. Serum IgA levels are generally higher than IgM, but much lower than IgG. In contrast, IgA levels in mucosal surfaces and secretions (including saliva and breast milk) are much higher than IgG. In particular, IgA can contribute up to 50% of protein in colostrum, which is the "first milk" that mothers give to newborns. Genetic sequence analysis and functional comparisons have shown that immunoglobulin A (IgA) is present in all mammals (placenta, marsupial and monocular) and birds. Humans, chimpanzees, gorillas, and gibbons have two IgA heavy chain constant region (Cα) genes that produce two subclasses, IgA1 and IgA2, while most other species examined (red chimpanzees, rhesus monkeys, and crabs) Monkeys, cattle, horses, pigs, dogs, mice, rats, acupuncture and possums have only one Cα gene similar to Cα2. Red gorillas that only have a single IgA like IgA1 may have lost their IgA2. For rabbits (rabbits), an interesting exception here is that it has 13 Cα genes, 12 of which appear to be expressed. A single IgA gene can also be considered to be present in most birds because they have been described in chickens and ducks that are considered to be one of the most primitive birds in existence. There are two IgA subclasses in the human body, namely IgA1 and IgA2, and the structural differences between the two are mainly in their hinge regions. The IgA1 molecule has a longer hinge region, which is a flexible stretched polypeptide located at the core of the antibody, which functions to divide the region responsible for the antigen binding region and the effector region. Compared to IgA1, IgA2 lacks the 13 amino acid sequence in the hinge region. The shorter hinge region better protects IgA2 from bacterial proteases than IgA1. This enhanced protection against protease digestion may explain why IgA2 predominates in many mucosal secretions (the ratio of IgA2 to IgA1 in the gut is 3:2), while more than 90% of serum IgA is in the IgA1 form. Allelic variation of IgA has been studied in some species, but remains to be studied in many other species. In humans, the IgA2 subclass has two (or possibly three) alleles. The two allotype (genetic) variants of IgA2 differ in the point of attachment between the heavy and light chains. Rhesus macaque IgA also showed allelic polymorphisms, while restriction fragment length polymorphism (RFLP) evidence indicated the presence of bovine IgA and equine IgA allotypes. Mouse IgA exists in different allelic forms and is characterized by its hinge region. Similarly, two allelic variants of porcine IgA differ in the hinge region. Both human IgA1 and IgA2 have membrane-bound forms (mIgA1 and mIgA2) containing the corresponding mα1 and mα2 heavy chains, which differ from α1 and α2 in three additional extensions from the CH3 domains of α1 and α2. The C-terminal domain, the outer membrane proximal domain (EMPD), the transmembrane domain (TMD), and the cytoplasmic domain (CytoD). These three C-terminal domains are collectively referred to as membrane-anchored peptide segments. Similar membrane-anchored peptide segments have also been identified in other Ig isotypes, including IgM, IgD, IgG, and IgE. In most Ig isoforms (except membrane IgA), these three domains are encoded by two additional exons called M1 and M2. Exon M1 encodes EMPD and TMD, while M2 encodes CytoD. In the case of membrane IgA, a single exon encodes EMPD, TMD and CytoD. The heavy chain mα1 is present in short and long isoforms, called mα1S and mα1L, which contain an additional 6 amino acid residues GSCSVA at the N-terminus of the extracellular domain (EMPD domain). According to the survey, in the Taiwanese population, in addition to the known mα1 allele, the fourth amino acid residue in the above six amino acid segments is S (SEQ ID NO: 1), and mα1 also has an allele. The fourth amino acid residue is C (SEQ ID NO: 2). Obviously, this newly identified allele is only found in the long isoform, mα1L, but not in the short isoform mα1S (due to the complete deletion of 6 amino acid stretches by mα1S). Since mα2 exists only as a short isoform, there is no allelic variation in its membrane exon. B cells carrying IgG and IgM appear in the early developmental stage, while B cells carrying IgA appear for the first time in about three months after birth. Although IgM and IgG plasma cells are usually found early in the second trimester, no IgA-producing cells were observed before the 32nd week of gestation. Serum IgA is usually not detected at birth and adult serum concentrations are not reached until puberty. In adults, most human plasma cells produce IgA. The IgA produced is more than the sum of all other immunoglobulin isotypes. Normal serum includes about 80% immunoglobulin G (IgG), about 15% immunoglobulin A (IgA), about 5% immunoglobulin M (IgM), and about 0.2% immunoglobulin D (IgD). ), and trace amounts of immunoglobulin E (IgE). Plasma IgA is produced by B lymphocytes in the bone marrow and some peripheral lymphoid organs. The half-life of plasma IgA is 3-6 days, while the half-life of IgG is 21 days. Since the plasma concentration of IgA is about one-fifth that of IgG, this means that the rate of synthesis of plasma IgG and IgA is similar. The antibody-secreting plasma cells and their immediate precursors (plasma cells) are produced in systemic and mucosal immune responses. In any unimmunized donor, plasma blasts and plasma cells are always detectable at low frequencies in human blood. At this steady state, 80% of plasmablasts and plasma cells express immunoglobulin A (IgA). About 40% of plasma cells in human bone marrow are non-migrating IgA and express β7 integrin and CCR10, suggesting that mucosal plasma cells contribute significantly to long-lived plasma cells that reside in the bone marrow. Systemic vaccination did not affect the number of peripheral IgA plasmablasts, suggesting that mucosal and whole body fluid immune responses are independently regulated (Blood (2009) 113: 2461-2469).anti- IgA antibody In one aspect, the invention provides an antibody or antigen-binding fragment thereof that specifically binds to membrane IgA. It will be appreciated that antibodies to membrane IgA as described herein will have a variety of applications. These applications include: diagnostic kits for the production of detection and diagnosis of IgA-related disorders and treatment of IgA-related disorders. In these cases, these antibodies can be linked to diagnostic or therapeutic agents, used as capture or competition agents in competitive assays, or used alone without the addition of other agents. The antibody can be mutated or modified as described further below. A. General Methods Methods for preparing and characterizing antibodies are well known in the art (see, for example, Antibodies: A Laboratory Manual, Cold Spring Harbor Laboratory, 1988; U.S. Patent 4,196,265). Methods for generating monoclonal antibodies (MAbs) typically begin in the same manner as polyclonal antibodies are prepared. The first step in both methods is to get the appropriate host immune. The immunogenicity of a given composition for immunization can vary, as is well known in the art. Therefore, it is often desirable to enhance the host immune system by coupling the peptide or polypeptide immunogen to the carrier. Exemplary and preferred carriers are keyhole limpet hemocyanin (KLH) and bovine serum albumin (BSA). Other albumins may also be used as a carrier, such as ovalbumin, mouse serum albumin or rabbit serum albumin. Methods for conjugating a polypeptide to a carrier protein are well known in the art and include glutaraldehyde, m-maleimidobenzimidyl-N-hydroxysuccinimide, carbodiimide, and Bis-diazobenzidine. As is well known in the art, the immunogenicity of a particular immunogenic composition can be enhanced by the use of non-specific stimulating agents (referred to as adjuvants) of the immune response. Exemplary and preferred adjuvants include complete Freund's adjuvant (non-specific stimulating agent for immune response (containing killed M. tuberculosis)), incomplete Freund's adjuvant, and aluminum hydroxide adjuvant. The production of antibodies that specifically bind to membrane IgA may be complicated by the presence of IgA and IgA-producing cells in the immunized host, which may negatively select IgA-recognizing antibodies during B-cell maturation. To eliminate this disorder, in some embodiments, an IgA-deficient animal (eg, a mouse that knocks out IgA) is used to immunize. The amount of immunogenic composition used to produce polyclonal antibodies will vary with the nature of the immunogen and the animal used for immunization. Multiple routes can be used to administer immunogens (subcutaneous, intramuscular, intradermal, intravenous, and intraperitoneal). The production of polyclonal antibodies can be monitored by sampling the blood of the immunized animal at various time points after immunization. A second booster injection can also be given. Repeat the process of strengthening and titration until the appropriate titer is reached. When the desired level of immunogenicity is obtained, the immunized animal can be bled and the serum can be isolated and stored, and/or the animal can be used to generate the MAb. After immunization, somatic cells (especially B lymphocytes (B cells)) having the potential to produce antibodies are selected for the MAb production protocol. These cells can be obtained from the spleen or lymph nodes of the biopsy or in the blood of the loop. The antibody-producing B lymphocytes from the immunized animal are then fused with cells of immortal myeloma cells, which are usually one of the same species as the immunized animal or human or human/mouse chimeric cells. . Myeloma cell lines suitable for use in fusion matrices that produce hybridomas are preferably non-antibody producing, have high fusion efficiency and have an enzyme deficiency that results in growth in certain selective media. In progress, these media only support the growth of the desired fused cells (hybridomas). As is known to those skilled in the art, any of a number of myeloma cells can be used (Goding, pp. 65-66, 1986; Campbell, pp. 75-83, 1984). A method of hybridizing an antibody-producing spleen or lymph node cell to a myeloma cell generally comprises: in a 2:1 ratio of somatic cells to myeloma cells in the presence of one or more agents (chemical or electrical) that promote cell membrane fusion Mixing (although the ratio can vary from about 20:1 to about 1:1, respectively). Kohler and Milstein (1975; 1976) describe fusion methods using Sendai virus, and Gefter et al. (1977) using polyethylene glycol (PEG) (eg, 37% (v/v) PEG). It is also suitable to use an electrically induced fusion method (Goding, pp. 71-74, 1986). Fusion programs usually produce low frequency live hybrids, approximately 1 x 10^-6 To 1×10^-8 . However, this does not pose a problem because live fusion hybrids differ from parental infusion cells (especially infused myeloma cells that would normally continue to divide indefinitely) by culturing in selective media. Selective media are typically tissue culture media containing agents that block de novo synthesis of nucleotides. Exemplary and preferred reagents are methotrexate, methotrexate and azaserine. Aminoguanidine and methotrexate block the de novo synthesis of purines and pyrimidines, while azase serine only blocks purine synthesis. When aminopterin or methotrexate is used, the medium is supplemented with hypoxanthine and thymidine as a source of nucleotides (HAT medium). In the case of the use of azaserine, the medium is supplemented with hypoxanthine. If the B cells are derived from the Epstein Barr virus (EBV) transformed human B cell line, ouabain is added to eliminate EBV transformed cell lines that are not fused to myeloma. A preferred selective medium is HAT or HAT containing ouabain. Only cells capable of operating the nucleotide salvage pathway survive in HAT medium. Myeloma cells are defective in key enzymes of the salvage pathway (eg, hypoxanthine phosphoribosyltransferase (HPRT)) and therefore they are not viable. B cells can operate a salvage pathway, but they have a limited life span in culture and usually die within about two weeks. Thus, cells that are viable in selective media are only hybrids formed by myeloma and B cells. When the B cells used for fusion are derived from a series of EBV-transformed B cells, ouabain is also used for drug selection in hybrids because EBV-transformed B cells are susceptible to drug killing, and the myeloma is selected for use. The partner is anti-wow. A particular hybridoma can be selected from the population of hybridomas provided by the culture. Typically, hybridoma selection is performed by culturing the cells by monoclonal dilution in a microtiter plate and then by testing each clone supernatant (after about 2 to 3 weeks) to obtain the desired reactivity. The assay should be sensitive, simple, and rapid, such as radioimmunoassay, enzyme immunoassay, cytotoxicity assay, plaque assay immunoassay, and the like. The selected hybridomas are then serially diluted or sorted by flow cytometry and cloned into individual antibody-producing cell lines, which can then be subjected to infinite propagation cloning to provide mAbs. Cell lines can be used for MAb production in two basic ways. Hybridoma samples can be injected into an animal (eg, a mouse) (typically into the peritoneal cavity). Optionally, the animal is primed with a hydrocarbon, especially an oil such as decane (tetramethylpentadecane) prior to injection. When human hybridomas are used in this manner, it is preferred to inject immunocompromised mice (e.g., SCID mice) to avoid tumor rejection. The injected animals produce tumors that secrete specific monoclonal antibodies produced by the fusion cell hybrids. The animal's body fluid (eg, serum or ascites) can then be collected to provide a high concentration of MAb. A single cell line can also be cultured in vitro, wherein the MAb is naturally secreted into the medium from which high concentrations of MAb can be readily obtained. Alternatively, human hybridoma cell lines can be used in vitro to produce immunoglobulins in cell supernatants. Cell lines can be engineered to grow in serum-free medium to optimize the ability to recover high purity human monoclonal immunoglobulins. If desired, the MAb produced by either method can be further purified using filtration, centrifugation, and various chromatographic methods (eg, FPLC) or affinity chromatography. Fragments of the monoclonal antibodies of the invention can be obtained from purified monoclonal antibodies by methods including digestion with an enzyme (eg, pepsin or papain) and/or chemical reduction of the disulfide bond. Alternatively, an automated peptide synthesizer can be used to synthesize the monoclonal antibody fragments encompassed by the present invention. Molecular cloning methods can also be used to generate monoclonal antibodies. To this end, RNA can be isolated from hybridoma lines and the antibody gene can be obtained by RT-PCR and cloned into an immunoglobulin expression vector. Alternatively, a combinatorial immunoglobulin phagemid library is prepared from RNA isolated from the cell line, and phagemids expressing the appropriate antibody are selected by panning using viral antigens. The advantage of this method over conventional hybridoma technology is that it can be generated and screened in a single round of about 10⁴ Multiple antibodies and new specificities can be created by combining the H and L chains, which further increases the chances of finding a suitable antibody. Other U.S. patents, each of which is hereby incorporated by reference in its entirety in its entirety in its entirety in its entirety in the the the the the the the the the the the the U.S. Patent 4,867,973 describes antibody-therapeutic agent conjugates. B. Membrane IgA antibodies Because of the abundant IgA in serum and mucosa, and IgA as the first line of defense has important functions in resisting pathogens, it is important to discover and develop antibodies that bind IgA to membranes but not soluble IgA. of. Thus, epitopes of such antibodies need to be present only on membrane-anchored IgA, but not in soluble IgA. The membrane-anchored form of human IgA (also known as membrane IgA or mIgA) differs from soluble IgA in that the membrane-anchored form of the heavy chain has three additional domains that extend from the CH3 domain, ie, the extracellular membrane. Proximal domain (EMPD), transmembrane domain (TMD), and cytoplasmic domain (CytoD). Thus, in some embodiments, an antibody or antigen-binding fragment thereof of the invention specifically binds to an epitope in EMPD, TMD or CytoD. In a preferred embodiment, an antibody or antigen-binding fragment thereof of the invention specifically binds to an epitope in EMPD. In one embodiment, an antibody or antigen-binding fragment thereof of the invention specifically binds to an epitope in EMPD of IgA1. In one embodiment, an antibody or antigen-binding fragment thereof of the invention specifically binds to an epitope in EMPD of IgA2. In one embodiment, an antibody or antigen-binding fragment thereof of the invention specifically binds to an epitope that can be found in EMPD of IgA1 and EMPD of IgA2. The IgA 1 heavy chain (mα1) exists as short and long isoforms, called mα1S and mα1L, which contain an additional 6 amino acid residues, GSCSVA, at the N-terminus of the extracellular domain (EMPD domain). According to the survey, in the Taiwanese population, in addition to the known mα1 allele (where the fourth amino acid residue in the above 6 amino acid stretch is S), mα1 also has an allele, of which the fourth The amino acid residue is C. This newly identified allele is only found in the long isoform, i.e., mα1L, but not in the short isoform, mα1S (due to the complete deletion of 6 amino acid stretches by mα1S). In contrast, the heavy chain (mα2) of IgA 2 exists only as a short isoform, and there is no allelic variation in its membrane exon. In certain embodiments, the antibodies and antibody-binding fragments provided by the invention are capable of specifically binding to membrane IgA while being determined by a plasmon resonance binding assay with a binding affinity of about 10^-6 M or lower (for example, 10^-6 M, 10^-8 M, 10^-9 M, 10^-10 M, 10^-11 M, 10^-12 M, 10^-13 M). Binding affinity can be K_D The value indicates that the value is calculated as the ratio of the dissociation rate to the binding rate when the binding between the antigen and the antigen-binding molecule reaches equilibrium (k)_Off /k_On ). Antigen binding affinity (eg, K_D The method can be suitably determined using suitable methods known in the art, for example, the method includes a plasmon resonance binding assay using an instrument such as Biacore (see, for example, Murphy et al., Current protocols in protein science, Chapter 19). , unit 19.14, 2006). In certain embodiments, the antibodies and antibody-binding fragments provided herein are capable of binding to IgA, as determined by ELISA, the IgA having from 0.001 μg/ml to 1 μg/ml (eg, 0.001 μg/ml to 0.5 μg/ml, 0.001 Gg/ml-0.2μg/ml, 0.001μg/ml-0.1μg/ml, 0.01μg/ml-0.2μg/ml, 0.01μg/ml-0.1μg/ml, 0.01μg/ml-0.05μg/ml, 0.01 EC of μg/ml-0.03μg/ml or 0.001μg/ml-0.01μg/ml)₅₀ (ie 50% binding concentration), or by FACS, with 0.01 μg/ml-1 μg/ml (eg, 0.01 μg/ml-0.5 μg/ml, 0.01 μg/ml-0.2 μg/ml, 0.05 μg/ml- EC of 1 μg/ml, 0.05 μg/ml-0.5 μg/ml or 0.05 μg/ml-0.2 μg/ml)₅₀ . Binding of antibodies to membrane IgA can be determined by methods known in the art such as ELISA, FACS, surface plasmon resonance, GST pulldown, epitope tagging, immunoprecipitation, Far-western blotting, fluorescence resonance energy transfer , Time-Resolved Fluorescence Immunoassay (TR-FIA), Radioimmunoassay (RIA), Enzyme Immunoassay, Latex Agglutination, Western Blot and Immunohistochemistry or other binding assays. In an exemplary embodiment, after washing away the unbound antibody, the test antibody (ie, the first antibody) is bound to the immobilized mIgA or mIgA-expressing cells, and the labeled second antibody is introduced, the labeled The diabodies can bind to the bound first antibody and thus enable detection thereof. When a fixed mIgA is used, it can be detected by a microplate reader, or when a cell expressing mIgA is used, it can be detected by using FACS analysis. In certain embodiments, when the antibody or antibody-binding fragment of the invention is administered to a subject, the antibody or antibody-binding fragment of the invention can eliminate or reduce IgA-expressing cells or block the subject (or The activation or immunosuppressive function of IgA-expressing B cells in the cancer microenvironment in the subject. In some embodiments, at least 50%, at least 60%, at least 70%, at least 80%, or at least 90% of IgA-expressing B cells are in the subject (or the cancer microenvironment in the subject) ) was eliminated. In some embodiments, the antibody or antibody-binding fragment of the invention blocks at least 50%, at least 60%, at least 70%, at least 80% or at least 90% of active or immunosuppressive function in IgA-expressing B cells . In some embodiments, the antibody eliminates or reduces IgA positive plasma cells. In some embodiments, the antibody eliminates or reduces IgA positive plasma cells. In some embodiments, the antibody eliminates or reduces IgA-converted B cells. In some embodiments, the antibody eliminates or reduces IgA plasmablasts. In some embodiments, the antibody eliminates or reduces IgA memory B cells. Although the antibodies of the invention are produced as antibodies to IgG, it may be useful to modify the constant regions to alter their function. The constant region of an antibody typically mediates binding of the antibody to host tissues or factors, including various cells of the immune system (eg, effector cells) and the first component (Clq) of the classical complement system. Thus, the term "antibody" includes intact immunoglobulins (and subtypes thereof) of the IgA, IgG, IgE, IgD, IgM type, wherein the light chain of the immunoglobulin can be of the kappa or lambda type. Within the light and heavy chains, the variable and constant regions are joined by a "J" region of about 12 or more amino acids, while the heavy chain also includes a "D" region of about 10 or more amino acids. See generally Fundamental Immunology Ch. 7 (Paul, W., ed., 2^Nd Ed. Raven Press, N.Y. 1989). C. Antibody Engineering In various embodiments, the sequence of the identified antibody can be selected for various reasons, such as improved expression, improved cross-reactivity, or reduced off-target binding. The following is a general discussion of techniques related to antibody engineering. The hybridoma can be cultured, then the cells are lysed and total RNA is extracted. Random hexanucleotides can be used with RT to generate a cDNA copy of the RNA, and then PCR is performed using multiple mixtures of PCR primers expected to be amplified for all human variable gene sequences. The PCR product can be cloned into the pGEM-T Easy vector and then sequenced by automated DNA sequencing using standard vector primers. Binding and neutralization assays can be performed using antibodies collected from hybridoma supernatants and purified by FPLC using a protein G column. Recombinant full-length IgG antibodies can be generated by subcloning heavy and light chain Fv DNA from cloning vectors into IgG plasmid vectors, transfecting into HEK293 cells or CHO cells, and collecting and purifying antibodies from HEK293 or CHO cell supernatants. . Rapid generation of antibodies using the same host cell and cell culture processes as the final cGMP manufacturing process can reduce the time required for process development. Antibody molecules include monovalent antibody derivatives, such as those produced by proteolytic cleavage of mAbs (eg, F(ab'), F(ab')₂ ), or comprise a single-chain immunoglobulin produced, for example, by recombinant methods. In one embodiment, the fragments can be combined with each other or with other antibody fragments or receptor ligands to form a "chimeric" binding molecule. Notably, such chimeric molecules may contain substituents that are capable of binding to different epitopes of the same molecule. Antibody Binding Modifications In related embodiments, an antibody is a derivative of the disclosed antibodies, for example, an antibody (eg, a chimeric or CDR-grafted antibody) comprising the same CDR sequences as the CDR sequences in the disclosed antibodies. Alternatively, it may be desirable to modify, for example, to introduce conservative changes into the antibody molecule. In making this change, the hydropathic index of the amino acid can be considered. The importance of hydrophilic amino acid indices in conferring biological functions on protein interactions is generally understood in the art (Kyte and Doolittle, 1982). It is acceptable that the relatively hydrophilic nature of the amino acid contributes to the secondary structure of the resulting protein, which in turn determines the interaction of the protein with other molecules (eg, enzymes, substrates, receptors, DNA, antibodies, antigens, etc.) . It is also understood in the art that similar amino acids can be effectively substituted based on hydrophilicity. U.S. Patent No. 4,554,101, the disclosure of which is incorporated herein by reference in its entirety, the entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire disclosure As detailed in U.S. Patent No. 4,554,101, the following hydrophilicity values have been assigned to amino acid residues: basic amino acids: arginine (+3.0), lysine (+3.0), and histidine (-0.5); acidic amino acids : aspartic acid (+3.0±1), glutamic acid (+3.0±1), aspartame (+0.2) and glutamine (+0.2); hydrophilic nonionic amino acid: serine (+0.3) ), aspartame (+0.2), glutamine (+0.2) and threonine (-0.4), sulfur-containing amino acids: cysteine (-1.0) and methionine (-1.3); hydrophobic non- Aromatic amino acids: valine (-1.5), leucine (-1.8), isoleucine (-1.8), valine (-0.5±1), alanine (-0.5) and glycine (0) Hydrophobic aromatic amino acids: tryptophan (-3.4), phenylalanine (-2.5) and tyrosine (-2.3). It will be understood that an amino acid may be substituted with another amino acid having similar hydrophilicity and produce a biologically or immunologically modified protein. Among these changes, amino acids having a hydrophilicity value of ±2 are preferably substituted, and amino acids within ±1 are particularly preferably substituted, and even more preferably, amino acids within ±0.5 are substituted. As noted above, amino acid substitutions are generally based on the relative similarity of amino acid side chain substituents, for example, their hydrophobicity, hydrophilicity, charge, size, and the like. Exemplary substitutions in view of the various aforementioned features are well known to those skilled in the art, including: arginine and lysine; glutamic acid and aspartic acid; serine and threonine; glutamine and Aspartate; and valine, leucine and isoleucine. Isotype modifications are also contemplated by the present invention. Different functions can be achieved by modifying the Fc regions to have different isotypes. For example, change to IgG₁ It increases the cytotoxicity of antibody-dependent cells, switching to type A improves tissue distribution, and switching to type M improves potency. Modified antibodies can be prepared by any technique known to those skilled in the art, including expression by standard molecular biology techniques or chemical synthesis of polypeptides. Methods for recombinant expression are mentioned elsewhere in this document. Fc region modifications are typically used to alter one or more functional properties of the antibody, such as serum half-life, complement binding, Fc receptor binding, and/or effector function (eg, antigen-dependent cellular toxicity), and the antibodies disclosed herein may also be Engineered to include modifications in the Fc region. Furthermore, the antibodies disclosed herein may be chemically modified (eg, one or more chemical moieties may be attached to the antibody) or may be modified to alter their glycosylation and be modified again to alter one or more functions of the antibody. characteristic. Each of these embodiments is discussed in detail below. The numbering of the residues in the Fc region is the numbering of the EU index of Kabat. Antibodies disclosed herein also include antibodies having a modified (or blocked) Fc region to provide altered effector function. See, for example, U.S. Patent No. 5,624,821; WO2003/086310; WO2005/120571; WO2006/0057702. Such modifications can be used to enhance or inhibit various responses of the immune system while potentially having beneficial effects in diagnosis and treatment. Alterations in the Fc region include amino acid changes (substitutions, deletions, and insertions), glycosylation or deglycosylation (deglycosylation may also be referred to as aglycosylation), and the addition of multiple Fc. Alterations to Fc can also alter the half-life of the antibody in the therapeutic antibody, resulting in a reduced frequency of administration, thereby increasing convenience and reducing the use of materials. It has been reported that this mutation eliminates the heterogeneity of disulfide bonds between heavy chains in the hinge region. In one embodiment, the hinge region of CH1 is modified such that the number of cysteine residues in the hinge region is increased or decreased. This method is further described in U.S. Patent 5,677,425. The number of cysteine residues in the CH1 hinge region is altered, for example, to facilitate assembly of the light and heavy chains or to increase or decrease the stability of the antibody. In another embodiment, the antibody is modified to increase its biological half life. Various methods are possible. For example, one or more of the following mutations can be introduced: T252L, T254S, T256F as described in U.S. Patent No. 6,277,375. Alternatively, to increase the biological half-life, the antibody can be altered in the CH1 or CL region to a salvage receptor binding epitope comprising two loops of the CH2 domain from the Fc region of IgG, as described in U.S. Patent Nos. 5,869,046 and 6,121,022. In yet another embodiment, the Fc region is altered by replacing at least one amino acid residue with a different amino acid residue to alter the effector function of the antibody. For example, different amino acid residues can be used to replace one or more amino acids selected from amino acid residues 234, 235, 236, 237, 297, 318, 320, and 322 such that the antibody has altered affinity for the effector ligand, but The antigen binding ability of the parent antibody is retained. For example, an effector ligand that requires altered affinity may be the Fc receptor or the C1 component of complement. This method is further described in U.S. Patent Nos. 5,624,821 and 5,648,260. In another embodiment, one or more amino acid residues within amino acid positions 231 and 239 are altered to alter the ability of the antibody to fix complement. This method is further described in PCT Publication WO 94/29351. In yet another embodiment, the Fc region is modified to increase or decrease the ability of the antibody to mediate antibody-dependent cellular cytotoxicity (ADCC) and/or to increase or decrease the antibody to Fcy by modifying one or more amino acids at the following position Affinity of the receptor: 238, 239, 243, 248, 249, 252, 254, 255, 256, 258, 264, 265, 267, 268, 269, 270, 272, 276, 278, 280, 283, 285, 286 , 289, 290, 292, 293, 294, 295, 296, 298, 301, 303, 305, 307, 309, 312, 315, 320, 322, 324, 326, 327, 329, 330, 331, 333, 334 , 335, 337, 338, 340, 360, 373, 376, 378, 382, 388, 389, 398, 414, 416, 419, 430, 434, 435, 437, 438 or 439. This method is further described in PCT Publication WO 00/42072. Furthermore, binding sites for FcγR1, FcγRII, FcγRIII and FcRn on human IgG1 have been mapped and variants with improved binding have been described. Specific mutations at positions 256, 290, 298, 333, 334 and 339 were shown to improve binding to FcyRIII. In addition, the following combinatorial mutations were shown to improve FcyRIII binding: T256A/S298A, S298A/E333A, S298A/K224A, and S298A/E333A/K334A. In one embodiment, by modifying residues 243 and 264, the Fc region is modified to reduce the ability of the antibody to mediate effector function and/or increase anti-inflammatory properties. In one embodiment, the Fc region of an antibody is modified by changing the residues at positions 243 and 264 to alanine. In one embodiment, by modifying residues 243, 264, 267, and 328, the Fc region is modified to reduce the ability of the antibody to mediate effector functions and/or increase anti-inflammatory properties. In yet another embodiment, the antibody comprises a specific glycosylation pattern. For example, an aglycosylated antibody can be prepared (ie, the antibody lacks glycosylation). For example, the glycosylation pattern of an antibody can be altered to increase the affinity or affinity of the antibody for the antigen. For example, such modification can be achieved by altering one or more glycosylation sites in the antibody sequence. For example, one or more amino acid substitutions can be made to cause one or more variable region frameworks to remove a glycosylation site, thereby eliminating glycosylation at that site. This glycosylation increases the affinity or affinity of the antibody for the antigen. See, for example, U.S. Patents 5,714,350 and 6,350,861. An antibody can also be prepared wherein the glycosylation pattern comprises a low fucosylated or nonfucosylated glycan, such as a low fucosylated antibody or a nonfucosylated antibody in a poly There is a reduced amount of fucosyl residues on the sugar. These antibodies may also include glycans having an increased amount of GlcNac bifurcation structure. This altered glycosylation pattern has been shown to increase the ADCC ability of antibodies. For example, such modification can be achieved by expressing an antibody in a host cell, wherein the glycosylation pathway has been genetically engineered to produce a glycoprotein having a particular glycosylation pattern. These cells have been described in the art and can be used as host cells for expression of the recombinant antibodies of the invention to produce antibodies with altered glycosylation. For example, the cell lines Ms704, Ms705 and Ms709 lack the fucosyltransferase gene FUT8 (α(1,6)-fucosyltransferase), whereby antibodies expressed in the Ms704, Ms705 and Ms709 cell lines can be There is a lack of fucose on the glycosyl group. The Ms704, Ms705 and Ms709 FUT8-/- cell lines were generated by targeting the disruption of the FUT8 gene in CHO/DG44 cells using two alternative vectors (see, U.S. Patent Publication No. 20040110704). As a further embodiment, EP 1 176 195 describes a cell line with a functionally disrupted FUT8 gene encoding a fucosyltransferase such that antibodies expressed in such a cell line can be reduced or eliminated by -1,6-bond-related enzymes exhibit low fucosylation. EP 1 176 195 also describes cell lines with low or no enzymatic activity (for example the rat myeloma cell line YB2/0 (ATCC CRL 1662)), which is used for N-binding to the Fc region of the antibody. Fucose is added to acetaminophen. PCT Publication WO 03/035835 describes a variant CHO cell line Lec13 cell which has reduced ability to link fucose to an Asn(297)-linked glycosyl group while also resulting in expression of antibodies in the host cell. Produces low fucosylation. Antibodies with modified glycosylation profiles can also be produced in eggs as described in PCT Publication WO 06/089231. Alternatively, antibodies having a modified glycosylation profile can be produced in plant cells, such as Lemna (U.S. Patent 7,632,983). U.S. Patent Nos. 6,998,267 and 7,388,081 disclose methods of producing antibodies in plant systems. PCT Publication WO 99/54342 describes cell lines engineered to express glycoprotein modified glycosyltransferases (eg, β(1,4)-N-acetylglucosyltransferase III (GnTIII)), thereby Antibodies expressed in engineered cell lines exhibit increased GlcNac bi-branched structure, resulting in increased ADCC activity by the antibody. Alternatively, a fucosidase can be used to cleave the fucose residue of the antibody; for example, a fucosidase alpha-L-fucosidase removes a fucosyl residue from the antibody. Antibodies disclosed herein also include antibodies produced in lower eukaryotic host cells, particularly fungal host cells (eg, yeast and filamentous fungi) that have been genetically engineered to produce mammals or humans. A glycoprotein of the glycosylation pattern. A particular advantage of these genetically modified host cells over currently used mammalian cell lines is the ability to control the glycosylation profile of glycoproteins produced in the cells, thereby producing glycoprotein compositions in which specific N-glycan structures are produced. Dominance (see, for example, U.S. Patents 7,029,872 and 7,449,308). These genetically modified host cells have been used to produce antibodies that have predominantly specific N-glycan structures. Furthermore, since fungi such as yeast or filamentous fungi lack the ability to produce fucosylated glycoproteins, unless the cells are further modified to include an enzymatic pathway that produces fucosylated glycoproteins, they are produced in these cells. The antibody will be deficient in fucose (see, for example, PCT Publication WO 2008112092). In a specific embodiment, the antibodies disclosed herein also include antibodies produced in lower eukaryotic host cells comprising fucosylated and nonfucosylated hybrid and complex N-glycans, Including two-branched and multi-branched glycosyl groups, including but not limited to N-glycans, such as GlcNAc(1-4)Man3GlcNAc2; Gal(1-4)GlcNAc(1-4)Man3GlcNAc2; NANA(1-4)Gal( 1-4) GlcNAc(1-4) Man3GlcNAc2. In a specific embodiment, the antibodies provided herein may have at least one hybrid N-glycan selected from the group consisting of GlcNAcMan5GlcNAc2, GalGlcNAcMan5GlcNAc2, and NANAGalGlcNAcMan5GlcNAc2. In a particular aspect, the hybrid N-glycan is the predominant N-glycan species in the composition. In other aspects, the hybrid N-glycan is a specific N-glycan species comprising about 30%, 40%, 50%, 60%, 70%, 80%, 90% of the composition, % of heterozygous N-glycans of 95%, 97%, 98%, 99% or 100. In a specific embodiment, the antibody provided herein has at least one complex N-glycan selected from the group consisting of GlcNAcMan3GlcNAc2, GalGlcNAcMan3GlcNAc2, NANAGalGlcNAcMan3GlcNAc2, GlcNAc2Man3GlcNAc2, GalGlcNAc2Man3GlcNAc2, Gal2GlcNAc2Man3GlcNAc2, NANAGal2GlcNAc2Man3GlcNAc2, and NANA2Gal2GlcNAc2Man3GlcNAc2. In a particular aspect, the complex N-glycan is the predominant N-glycan species in the composition. In other aspects, the complex N-glycan is a specific N-glycan species comprising about 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95 in the composition. %, 97%, 98%, 99% or 100% of the composite N-glycan. In a particular embodiment, the N-glycan is fucosylated. In general, fucose forms an α1,3-bond with GlcNAc at the reducing end of the N-glycan, forms an α1,6-bond with the GlcNAc at the reducing end of the N-glycan, and is at the non-reducing end of the N-glycan with Gal. The α1,2-bond is formed, the α1,3-bond of GlcNac at the non-reducing end of the N-glycan, or the α1,4-bond with GlcNAc at the non-reducing end of the N-glycan. Thus, in a particular aspect of the glycoprotein composition described above, the glycoform is an alpha 1,3-bond or alpha 1,6-chain fucose to produce a moiety selected from the group consisting of Man5GlcNAc2 (Fuc), GlcNAcMan5GlcNAc2 (Fuc), Man3GlcNAc2 (Fuc), a glycoform in GlcNAcMan3GlcNAc2 (Fuc), GlcNAc2Man3GlcNAc2 (Fuc), GalGlcNAc2Man3GlcNAc2 (Fuc), Gal2GlcNAc2Man3GlcNAc2 (Fuc), NANAGal2GlcNAc2Man3GlcNAc2 (Fuc), and NANA2Gal2GlcNAc2Man3GlcNAc2 (Fuc); the glycoform is α1,3-bond or α1,4-bond, The production is selected from the group consisting of GlcNAc (Fuc) Man5GlcNAc2, GlcNAc (Fuc) Man3GlcNAc2, GlcNAc2 (Fuc1-2) Man3GlcNAc2, GalGlcNAc2 (Fuc1-2) Man3GlcNAc2, Gal2GlcNAc2 (Fuc1-2) Man3GlcNAc2, NANAGal2GlcNAc2 (Fuc1-2) Man3GlcNAc2 and NANA2Gal2GlcNAc2 (Fuc1 -2) a glycoform in Man3GlcNAc2; or a glycoform of α1,2-bond fucose to produce a member selected from the group consisting of Gal(Fuc)GlcNAc2Man3GlcNAc2, Gal2(Fuc1-2)GlcNAc2Man3GlcNAc2, NANAGal2(Fuc1-2)GlcNAc2Man3GlcNAc2, and NANA2Gal2 ( Fuc1-2) Glycoform in GlcNAc2Man3GlcNAc2. In other aspects, the antibody comprises a high mannose N-glycan including, but not limited to, Man8GlcNAc2, Man7GlcNAc2, Man6GlcNAc2, Man5GlcNAc2, Man4GlcNAc2, or an N-glycan consisting of a Man3GlcNAc2 N-glycan structure. In other aspects of the above, the complex N-glycans also include fucosylated and nonfucosylated bi-branched and multi-branched species. The terms "N-glycan" and "glycoform" as used in the present invention are used interchangeably and refer to N-linked oligosaccharides, for example, by aspartate-N-acetylglucosamine linkages and polypeptides. An oligosaccharide linked to a guanamine residue. The N-linked glycoprotein contains an N-acetylglucosamine residue attached to the guanamine nitrogen of the aspartic acid residue in the protein. D. Purification of Antibodies In certain embodiments, the antibodies of the invention can be purified. The term "purified" as used in the present invention means that the composition can be separated from other components, wherein the protein is purified to any extent relative to its naturally available state. Thus, purified protein also refers to proteins that are detached from their naturally occurring environment. When the term "substantially purified" is used, the name means that the protein or peptide in the composition forms the major component of the composition, for example, in the composition comprising about 50%, about 60%, about 70%, about 80%, about 90%, about 95% or more protein. Protein purification techniques are well known to those skilled in the art. These techniques involve, at one level, the coarse fractionation of polypeptide and non-polypeptide fractions by the cellular environment. After separating the polypeptide from other proteins, the target polypeptide can be further purified using chromatographic and electrophoretic techniques to achieve partial or complete purification (or purification to homogeneity). Analytical methods particularly suitable for the preparation of pure peptides are ion exchange chromatography, exclusion chromatography, polypropylene guanamine gel electrophoresis, isoelectric focusing. Other methods for protein purification include: precipitation with ammonium sulfate, PEG, antibodies, etc. or by thermal denaturation followed by centrifugation; gel filtration, reversed phase, hydroxyapatite and affinity chromatography; and these and other techniques The combination. In purifying an antibody of the invention, it may be desirable to express the polypeptide in a prokaryotic or eukaryotic expression system and to use denaturing conditions to extract the protein. A peptide from other cellular components can be purified using an affinity column that binds to the labeled portion of the polypeptide. The order in which the various purification steps are performed can be altered, as is generally known in the art, or certain steps can be omitted and still produce suitable methods for preparing substantially purified proteins or peptides. Typically, an agent that binds to the Fc portion of the antibody (ie, Protein A) is used to isolate the intact antibody. Alternatively, the antigen can be used to simultaneously purify and select the appropriate antibody. These methods typically utilize a selection agent that is combined with a carrier such as a column, screening program or beads. The antibody binds to the carrier, removes contaminants (eg, washes off) and releases the antibody by applying conditions (salt, heat, etc.). Various methods for quantifying the degree of purification of a protein or peptide are known to those skilled in the art in accordance with the present invention. For example, these include determining the specific activity of the active fraction or assessing the amount of polypeptide within the fraction by SDS/PAGE analysis. Another method for assessing the purity of a fraction is to calculate the specific activity of the fraction and compare it to the specific activity of the initial extract to calculate the purity. Of course, the actual unit used to indicate the amount of activity will depend on the particular assay technique chosen for purification and whether the expressed protein or peptide exhibits detectable activity. It is known that the migration of polypeptides can vary with different conditions of SDS/PAGE, sometimes significant (Capaldi et al., 1977). It will therefore be appreciated that the apparent molecular weight of the purified or partially purified expression product will vary under different electrophoresis conditions.Antibody composition In another aspect, the invention provides a composition comprising an antibody that specifically binds to membrane-bound IgA. These compositions comprise a pharmaceutical composition and an antibody conjugate, for example, for diagnostic or therapeutic purposes. A. Pharmaceutical Compositions The pharmaceutical compositions provided herein comprise a prophylactically or therapeutically effective amount of an antibody or fragment thereof and a pharmaceutically acceptable carrier. In a specific embodiment, the term "pharmaceutically acceptable" means approved by a regulatory agency of the federal or state government or listed in the United States Pharmacopoeia or other recognized pharmacopoeia for use in animals, more particularly humans. The term "carrier" refers to a diluent, excipient or carrier with which the therapeutic agent is administered. Such pharmaceutical carriers can be sterile liquids (eg, water and oil), including those of petroleum, animal, vegetable or synthetic origin (eg, peanut oil, soybean oil, mineral oil, sesame oil, etc.). Water is a specific carrier when the pharmaceutical composition is administered intravenously. Saline solutions and aqueous dextrose and glycerol solutions can also be employed as liquid carriers, especially in injectable solutions. Other suitable components of the carrier may include, for example, antioxidants, humectants, fillers, binders, disintegrants, buffers, preservatives, lubricants, flavoring agents, thickeners, colorants, emulsifiers or Stabilizers (eg, sugars and cyclodextrins). Suitable antioxidants may include, for example, methionine, ascorbic acid, EDTA, sodium thiosulfate, platinum, catalase, citric acid, cysteine, thioglycerol, thioglycolic acid, thiosorbitol, Butylated hydroxyanisole, butylated hydroxytoluene and/or propyl gallate. As disclosed herein, the inclusion of one or more antioxidants (eg, methionine) in a composition comprising an antibody or antigen-binding fragment provided herein and a conjugate can reduce oxidation of the antibody or antigen-binding fragment. The reduction in oxidation prevents or reduces the loss of binding activity or binding affinity, thereby improving antibody stability and maximizing shelf life. Accordingly, in certain embodiments, provided compositions comprise one or more of the antibodies or antigen-binding fragments disclosed herein and one or more antioxidants (eg, methionine). Also provided is a method for avoiding oxidation, prolonging its shelf life and/or improving the efficacy of an antibody or antigen-binding fragment provided by the present invention by administering an antibody or antigen-binding fragment to one or more antioxidants (eg, methionine) ) Mix to complete. Suitable humectants include ethylene glycol, glycerin or sorbitol. Suitable lubricants include, for example, acetamyl ester wax, hydrogenated vegetable oil, magnesium stearate, methyl stearate, mineral oil, polyoxyethylene-polyoxypropylene copolymer, polyethylene glycol, polyvinyl alcohol, ten Sodium dialkyl sulfate or white wax or a mixture of two or more thereof. Suitable emulsifiers include carbomer, polyoxyethylene-20-stearyl ether, cetostearyl alcohol, cetyl alcohol, cholesterol, diethylene glycol stearate, glyceryl stearate, hydroxypropyl group Cellulose, lanolin, polyoxyethylene lauryl ether, methyl cellulose, polyoxyethylene stearate, polysorbate, propylene glycol monostearate, sorbitan ester or stearic acid . For further explanation, the pharmaceutically acceptable carrier may include, for example, an aqueous carrier (eg, sodium chloride injection, Ringer's injection, isotonic glucose injection, sterile injectable water or dextrose and lactated Ringer's) Injection), non-aqueous carrier (for example, plant-derived fixed oil, cottonseed oil, corn oil, sesame oil or peanut oil, antibacterial agent for bacteriostatic or bacteriostatic concentration), isotonic agent (for example, sodium chloride or glucose), Buffers (eg, phosphate or citrate buffers), antioxidants (eg, sodium bisulfate), local anesthetics (eg, procaine hydrochloride), suspending agents, and dispersing agents (eg, carboxymethyl cellulose) Sodium, hydroxypropylmethylcellulose or polyvinylpyrrolidone), emulsifier (eg, polysorbate 80 (TWEEN-80)), chelating agent (eg, EDTA (ethylenediaminetetraacetic acid) or EGTA (ethylene) Alcoholic acid), ethanol, polyethylene glycol, propylene glycol, sodium hydroxide, hydrochloric acid, citric acid or lactic acid). The antimicrobial agent used as a carrier may be added to the pharmaceutical composition in the form of a multi-dose container comprising phenols or cresols, mercury, benzyl alcohol, chlorobutanol, methyl paraben and p-hydroxybenzene. Methyl formate, thimerosal, benzalkonium chloride and benzethonium chloride. Suitable excipients can include, for example, water, saline, dextrose, glycerol or ethanol. Suitable non-toxic auxiliary substances may include, for example, wetting or emulsifying agents, pH buffering agents, stabilizers, solubility enhancers or such as sodium acetate, sorbitan monolaurate, triethanolamine oleate or cyclodextrin. Reagents. The pharmaceutical composition may be a liquid solution, suspension, emulsion, lotion, foam, pill, capsule, tablet, sustained release formulation, ointment, cream, paste, gel, spray, aerosol or powder. Oral formulations may include standard carriers such as pharmaceutical grade mannitol, lactose, starch, magnesium stearate, polyvinylpyrrolidone, sodium saccharin, cellulose, magnesium carbonate, and the like. In certain embodiments, the pharmaceutical compositions are formulated into injectable compositions. The injectable pharmaceutical compositions may be prepared in any conventional form, for example, a liquid solution, suspension, emulsion or solid form suitable for the production of liquid solutions, suspensions or emulsions. Formulations for injection may include sterile and/or non-pyrolyzed solutions for injection, ie, sterile dry soluble products (eg, lyophilized powder) to be mixed with the solvent prior to use, including subcutaneously injected tablets, ie for injection. Sterile suspensions, sterile dry insoluble products to be mixed with carriers prior to use, and sterile and/or non-pyrolyzed emulsions. These solutions may be aqueous or non-aqueous solutions. In certain embodiments, the unit dose parenteral formulation is packaged in an ampoule, vial or syringe with a needle. As is known and practiced in the art, all formulations for parenteral administration should be sterile rather than pyrolyzed. In certain embodiments, a sterile lyophilized powder is prepared by dissolving an antibody or antigen-binding fragment as disclosed herein in a suitable solvent. The solvent may contain excipients which improve the stability or other pharmacological components of the powder or reconstituted solution prepared from the powder. Excipients that may be used include, but are not limited to, water, dextrose, sorbitol, fructose, corn syrup, xylitol, glycerin, glucose, sucrose, or other suitable agents. In one embodiment, the solvent may contain a buffer of about neutral pH, such as citrate, sodium phosphate or potassium phosphate or other such buffers known to those skilled in the art. The solution is then sterile filtered and then lyophilized under standard conditions known to those skilled in the art to provide the desired formulation. In one embodiment, the resulting solution is dispensed into vials for lyophilization. Each vial may contain a single dose or multiple doses of an anti-IgA antibody or antigen-binding fragment thereof, or a combination thereof. A small excess overfill vial required for a dose or set of doses (e.g., about 10%) is acceptable for accurate sampling and precise dosing. The lyophilized powder can be stored under suitable conditions, for example, at about 4 ° C to room temperature. Reconstitution of the lyophilized powder using water for injection provides a formulation for parenteral administration. In one embodiment, sterile and/or non-pyrolyzed water or other liquid suitable carrier is added to the lyophilized powder for reconstitution. The exact amount will depend on the therapy chosen and can be determined empirically. B. Antibody Conjugates The antibodies of the invention can be linked to at least one agent to form an antibody conjugate. In order to increase the efficacy of an antibody molecule as a diagnostic or therapeutic agent, at least one desired molecule or moiety is typically linked or covalently bound or complexed. Such molecules or moieties can be, but are not limited to, at least one effector molecule or reporter molecule. An effector molecule comprises a molecule having a desired activity (eg, cytotoxic activity). Non-limiting embodiments of effector molecules attached to the antibody include toxins, antineoplastic agents, therapeutic enzymes, radionuclides, antiviral agents, chelating agents, cytokines, growth factors, and oligonucleotides or polynucleotides. Instead, the reporter is defined as any moiety that can be detected using an assay. Non-limiting embodiments of reporter molecules conjugated to an antibody include enzymes, radioactive labels, haptens, fluorescent labels, phosphorescent molecules, chemiluminescent molecules, chromophores, photoaffinities, colored particles or ligands (eg, organisms) Prime). Antibody conjugates are generally preferred for use as diagnostic agents. Antibody diagnostics generally fall into two categories, those used for in vitro diagnostics (eg, for various immunoassays) and those used in in vivo diagnostic protocols (commonly referred to as "antibody-directed imaging"). A number of suitable imaging agents are known in the art, as well as methods of attaching them to antibodies (see, for example, U.S. Patent Nos. 5,021,236, 4,938,948 and 4,472,509). The imaging moiety used can be a paramagnetic ion, a radioisotope, a fluorescent dye, an NMR detectable substance, and an X-ray imaging agent. In the case of paramagnetic ions, the following exemplary ions may be involved: chromium (III), manganese (II), iron (III), iron (II), cobalt (II), nickel (II), copper (II), ruthenium. (III), cerium (III), cerium (III), cerium (III), vanadium (II), cerium (III), cerium (III), cerium (III) and/or cerium (III), of which cesium is particularly preferred. . Ions useful in other environments (eg, X-ray imaging) include, but are not limited to, cerium (III), gold (III), lead (II), especially cerium (III). In the case of radioisotopes for therapeutic and/or diagnostic applications,²¹¹ Oh,¹⁴ carbon,⁵¹ chromium,³⁶ chlorine,⁵⁷ cobalt,⁵⁸ Cobalt, copper⁶⁷ ,¹⁵² Eu, gallium⁶⁷ ,³ Hydrogen, iodine¹²³ ,iodine¹²⁵ ,iodine¹³¹ ,indium¹¹¹ ,⁵⁹ iron,³² phosphorus,¹⁸⁶ rhenium,¹⁸⁸ rhenium,⁷⁵ selenium,³⁵ sulfur,^99m 鍀 and / or⁹⁰ yttrium. In certain embodiments,¹²⁵ I is usually preferred, and^99m m鍀 and/or¹¹¹ Indium is also preferred because of their low energy and suitable for long range detection. Radiolabeled monoclonal antibodies of the invention can be produced according to methods well known in the art. For example, monoclonal antibodies can be iodinated by contact with sodium iodide and/or potassium iodide and a chemical oxidant such as sodium hypochlorite or an enzyme oxidant such as lactoperoxidase. The monoclonal antibody according to the present invention can be used by a ligand exchange method^99m The label is labeled, for example, by reducing the perrhenate with a stannous solution, chelated the reduced ruthenium onto a Sephadex column, and applying the antibody to the column. Alternatively, direct labeling techniques can be used, for example, by culturing perrhenate, reducing agents (eg, SNCl)₂ ), buffer solution (such as sodium phthalate solution) and antibodies to complete. An intermediate functional group commonly used to bind a radioisotope present as a metal ion to an antibody is diethylenetriaminepentaacetic acid (DTPA) or ethylenediaminetetraacetic acid (EDTA). Fluorescent labels considered for use as conjugates include Alexa 350, Alexa 430, AMCA, BODIPY 630/650, BODIPY 650/665, BODIPY-FL, BODIPY-R6G, BODIPY-TMR, BODIPY-TRX, Cascade Blue, Cy3 , Cy5, 6-FAM, fluorescein isothiocyanate, HEX, 6-JOE, Oregon Green 488, Oregon Green 500, Oregon Green 514, Pacific Blue, REG, Rhodamine Green, Rhodamine Red, Renographin, ROX, TAMRA , TET, Tetramethylrhodamine and/or Texas Red. Another class of antibody conjugates contemplated in the present invention are antibody conjugates that are primarily used in vitro, wherein the antibody is linked to a secondary binding ligand and/or to an enzyme (enzyme tag) after contact with the chromogenic substrate. Produce colored products. Suitable embodiments of the enzyme include urease, alkaline phosphatase, (horseradish) hydroperoxidase or glucose oxidase. Preferred secondary binding ligands are biotin and avidin as well as streptavidin compounds. The use of such markers is well known to those skilled in the art and is described, for example, in U.S. Patent Nos. 3,817,837, 3,850,752, 3,939,350, 3,996,345, 4,277,437, 4,275,149, and 4,366,241. Another known method of molecular site-specific attachment to an antibody involves reacting the antibody with a hapten-based affinity tag. Basically, a hapten-based affinity tag reacts with an amino acid in an antigen binding site to disrupt the site and block specific antigenic responses. However, this may not be advantageous as it causes the antibody conjugate to lose antigen binding. Azide-containing molecules can also be used to form covalent bonds with proteins by reactive nitrene intermediates produced by low intensity ultraviolet light (Potter and Haley, 1983). In particular, 2- and 8-azido analogs of purine nucleotides have been used as site-directed light probes to identify nucleotide-binding proteins in crude cell extracts (Owens & Haley, 1987; Atherton et al., 1985). . 2- and 8-azidonucleotides have also been used to map the nucleotide binding domain of purified proteins (Khatoon et al., 1989; King et al., 1989; Dholakia et al., 1989) and can be used as antibodies. Binding agent. Several methods are known in the art for attaching or conjugating an antibody to its conjugate moiety. Some joining methods involve the use of metal chelates, for example, using organic chelating agents such as diethylene triamine pentaacetic anhydride (DTPA); ethylene triamine tetraacetic acid; N-chloro-p-toluenesulfonamide; and / Or tetrachloro-3α-6α-diphenylglycine-3 linked to an antibody (U.S. Patent Nos. 4,472,509 and 4,938,948). Monoclonal antibodies can also be reacted with the enzyme in the presence of a coupling reagent such as glutaraldehyde or periodate. A conjugate having a luciferin label is prepared in the presence of these coupling agents or by reaction with an isothiocyanate. In U.S. Patent 4,938,948, monoclonal antibodies are used to image breast tumors and a linker (e.g., methyl p-hydroxybenzinate or N-succinimido-3-(4-hydroxyphenyl) is used. Propionate) binds the detectable imaging moiety to the antibody. In other embodiments, it has been contemplated to use a reaction condition that does not alter the binding site of the antibody to derive an immunoglobulin by selectively introducing a thiol group in the Fc region of the immunoglobulin. Antibody conjugates produced according to this method have been disclosed to exhibit improved longevity, specificity and sensitivity (U.S. Patent 5,196,066, incorporated herein by reference). Site-specific attachment of effector or reporter molecules, wherein the reporter or effector molecule is conjugated to a carbohydrate residue in the Fc region, has also been disclosed in the literature (O'Shannessy et al., 1987). It has been reported that this method produces promising antibodies for diagnosis and treatment and is currently undergoing clinical evaluation.Instructions In another aspect, the invention also provides a method of using the antibodies or antigen-binding fragments of the invention to diagnose or treat an IgA-related disorder. A. IgA-associated disorder "IgA-associated disease" as used herein refers to any disease caused, aggravated or otherwise associated with an increase or decrease in expression or activity of an IgA or IgA-expressing cell. The condition associated with IgA or IgA-expressing cells can be an immune-related disease or condition, infection, and cancer. In some embodiments, the IgA-related disorder is IgA nephropathy (IgAN), allergic purpura (HSP), celiac disease, or cancer. IgA nephropathy (IgAN) is the most common form of human glomerulonephritis worldwide, characterized by the deposition of IgA in the glomerulus. Although the mechanism of human IgA nephropathy has not been fully elucidated, a decrease in the number of high serum IgA levels, enhanced IgA-specific Th cells, and IgA-specific regulatory T cells indicates that patients with this disease have a fundamental disorder of IgA production. In addition, the clinical relevance of recurrence of mucosal infections, elevated serum antibody titers to respiratory pathogens, and dietary components of these patients suggest that mucosal immunity may also be involved in the pathogenesis of IgA nephropathy. In some embodiments, the IgA-related disorder is associated with or associated with an IgA deficiency, the most common primary immunoglobulin deficiency. The prevalence of IgA deficiency in Caucasians is about one in 500, and is rare in some Asian populations. Among healthy blood donors, the prevalence of IgA deficiency ranges from one of 328-633 of European descent to 5,000 of China and 18,500 of Japan and even lower in India. Primary IgA deficiency is caused by a defect in terminal lymphocyte differentiation, resulting in insufficient production of serum and mucosal IgA; the affected individual has a normal IgA gene. Many non-immunoglobulin genes are associated with IgA deficiency. Many autoimmune diseases are associated with primary IgA deficiency. The most common related phenomenon is associated with celiac disease (CD), which is of special significance because CD is usually diagnosed by detecting specific IgA antibodies that are clearly deficient in IgA deficiency. Serum samples from subjects with IgA deficiency who do not exhibit any autoimmune disease usually contain autoantibodies. It is suggested that subjects with IgA deficiency with anti-food antibodies may have enhanced gastrointestinal antigenic absorption and that food-derived antigens may cross-react with autoantigens. Molecular modeling of gut microbial antigens can also play a role. It has been reported that a significant proportion of individuals with IgA deficiency have anti-IgA antibodies in their serum. For this reason, blood or blood products given to individuals with IgA deficiency can cause severe or even fatal transfusion reactions, although such reactions are rare. (Ann. Clin. Biochem. 2007; 44: 131-139). In fact, IVIG absorbed by IgA has been used to infuse patients with IgA deficiency associated with IgG or specific antibody deficiency. Most individuals with IgA deficiency are not overly susceptible to infection unless IgG2 is under-produced. When IgA and IgG subtype defects occur simultaneously, there is a significant incidence, mainly manifested as recurrent pulmonary sinus infection. The non-essentiality of IgA may reflect the ability of IgM to replace IgA as the primary antibody in secretions, and indeed an increased number of IgM-producing plasma cells are found in the intestinal mucosa of people with IgA deficiency. Since IgM is a J-linked polymer, IgM produced in the intestinal mucosa is efficiently bound by pIgR and transported as secretory IgM through epithelial cells into the intestinal lumen. The importance of this alternative mechanism has been shown in knockout mice. Animals lacking IgA alone have a normal phenotype, but animals lacking pIgR are susceptible to mucosal infection. Humans have never reported a genetic deletion of pIgR, suggesting that this deficiency is fatal. A murine model with IgA deficiency has been established by targeted deletion of the IgA transition and constant regions in embryonic stem cells. B cells from IgA-deficient mice are unable to produce IgA in response to TGF-β in vitro. IgA-deficient mice express higher levels of IgM and IgG in serum and gastrointestinal secretions, and lower levels of IgE expression in serum and lung secretions. The expression of the IgG subclass is complex, the most consistent finding is an increase in IgG2b and a decrease in IgG3 in serum and secretions. No detectable IgA antibodies were observed following mucosal immunization against influenza; however, elevated levels of IgM antibodies were observed in both serum and secretions compared to wild-type mice. Lymphoid tissue development and T and B lymphocyte function appear to be normal. Although there is no IgA in these germinal centers or lamina propria, the Peyer plaques in IgA-deficient mice develop well and have prominent germinal centers. Lymphocytes from IgA-deficient mice respond to T and B cell mitosis comparable to wild-type mice, whereas T cells from IgA-deficient mice produce comparable levels of IFN- and IL-4 mRNA and protein. In conclusion, mice with targeted deletions of the IgA transition and constant regions are completely deficient in IgA and exhibit altered expression of other Ig isoforms, particularly IgM, IgG2b, IgG3 and IgE, in addition to normal lymphocytes. Development, proliferative responses, and cytokine production (The Journal of Immunology (1999) 162: 2521-2529). In certain embodiments, the IgA-related disorder is cancer. In certain embodiments, the cancer comprises, for example, non-small cell lung cancer (squamous/non-squamous), small cell lung cancer, renal cell carcinoma, colorectal cancer, colon cancer, ovarian cancer, breast cancer (including a substrate) Breast, ductal, and lobular breast cancer, pancreatic cancer, stomach cancer, bladder cancer, esophageal cancer, mesothelioma, melanoma, head and neck cancer, thyroid cancer, sarcoma, prostate cancer, glioblastoma, cervical cancer, thymic carcinoma , melanoma, myeloma, fungal disease fungus, Merkel cell carcinoma (MCC), hepatocellular carcinoma (HCC), fibrosarcoma, mucinous sarcoma, liposarcoma, chondrosarcoma, osteosarcoma and other sarcomas, synovial, interstitial Dermatoma, Ewing's tumor, leiomyosarcoma, rhabdomyosarcoma, lymphoid malignancy, basal cell carcinoma, adenocarcinoma, sweat gland cancer, medullary thyroid carcinoma, papillary thyroid carcinoma, pheochromocytoma sebaceous gland carcinoma, papillary carcinoma, nipple Adenocarcinoma, medullary carcinoma, bronchial carcinoma, liver cancer, cholangiocarcinoma, choriocarcinoma, nephroblastoma, cervical cancer, testicular tumor, seminoma. In certain embodiments, the blood disorder includes, for example, classic Hodgkin's lymphoma (CHL), primary mediastinal large B-cell lymphoma, T-cell/tissue cell-rich B-cell lymphoma, acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), acute myeloid leukemia, acute myeloid leukemia and myeloblasts, promyelocytes, myelomonocytic cells, monocytic leukemia and erythroleukemia, chronic granulocytes (granulocytes) Leukemia, chronic myeloid leukemia, chronic lymphocytic leukemia, polycythemia vera, mast cell-derived tumors, EBV-positive and negative PTLD, diffuse large B-cell lymphoma (DLBCL), serous lymphoma, extranodal NK /T-cell lymphoma, nasopharyngeal carcinoma, HHV8-associated primary effusion lymphoma, non-Hodgkin's lymphoma, multiple myeloma, Waldenstrom's macroglobulinemia, heavy chain disease, bone marrow Proliferative disorders, hairy cell leukemia and myelodysplasia, central nervous system tumors (CNS) (eg, primary central nervous system lymphoma, spinal cord tumor, brainstem glia) Tumor, astrocytoma, medulloblastoma, craniopharyngioma, ependymoma, pineal tumor, hemangioblastoma, acoustic neuroma, oligodendroglioma, hemangioma, melanoma, neuromuscular Cell tumors and retinoblastoma, etc.). B. Administration of Antibodies In some embodiments, the invention provides a method for treating an immunoglobulin-A (IgA)-related disease in a subject, the method comprising administering to the subject a therapeutically effective amount of a specific An antibody that binds to IgA or an antigen-binding fragment thereof, thereby eliminating or reducing IgA-expressing cells or blocking the activation or immunosuppressive function of IgA-expressing B cells in the subject. Therapeutic antibodies act through several mechanisms. In addition to blocking the binding of ligands to inhibitor receptors in immune cells, such as antibodies that block PD-1, PD-L1 and CTLA-4, some are by removing proteins from the loop or diseased tissue or through The ligand is prevented from binding to an activated or adhesive receptor present on the immune cell. Examples of these include anti-TNF (Humira et al), anti-IgE (Xolair), anti-VEGF (Avastin, etc.), anti-IL17A (Cosentyx), anti-IL5 (NUCALA, CINQAIR), anti-IL-6 (Sylvant), anti-IL6 receptor Actemra and anti-integrin (Tysabri, Entyvio, etc.) and the like. Therapeutic antibodies also act by causing the consumption of pathogenic cell types by ADCC, CDC, phagocytosis, apoptosis, necrosis or necrotic apoptosis. For example, anti-CD20 (Rituxan, Gazyva, Octevus) antibodies have been shown to reduce B cells. A therapeutically effective amount of an antibody or antigen-binding fragment thereof provided by the present invention (when used alone or in combination with other agents such as chemotherapeutic agents) depends on various factors known in the art, such as the type of disease to be treated, the antibody Type, weight, age, past medical history, current medication, subject's health status, immune status and cross-reactivity, likelihood of allergy, sensitivity and adverse side effects, as well as route of administration and type, severity and development of the disease and indications Discretion of the physician or veterinarian. In certain embodiments, an antibody or antigen-binding fragment provided herein can be administered a therapeutically effective dose of from about 0.001 mg/kg to about 100 mg/kg, one or more times a day (eg, about 0.001 per day or multiple administrations) Mg/kg, about 0.3 mg/kg, about 0.5 mg/kg, about 1 mg/kg, about 3 mg/kg, about 5 mg/kg, about 10 mg/kg, about 15 mg/kg, about 20 mg/kg, about 25 mg/kg About 30 mg/kg, about 35 mg/kg, about 40 mg/kg, about 45 mg/kg, about 50 mg/kg, about 55 mg/kg, about 60 mg/kg, about 65 mg/kg, about 70 mg/kg, about 75 mg/kg. About 80 mg/kg, about 85 mg/kg, about 90 mg/kg, about 95 mg/kg or about 100 mg/kg). In certain embodiments, the antibody or antigen-binding fragment is administered at a dose of about 50 mg/kg or less, and in certain embodiments, the dose is 20 mg/kg or less, 10 mg/kg or less. 3 mg/kg or lower, 1 mg/kg or lower, 0.3 mg/kg or lower, 0.1 mg/kg or lower, or 0.01 mg/kg or lower, or 0.001 mg/kg or lower. In certain embodiments, the administered dose can be varied during the course of treatment. For example, in certain embodiments, the initial administration dose can be higher than the subsequent administration dose. In certain embodiments, the dosage administered can vary depending on the response of the subject as the course of the treatment progresses. The dosage regimen can be adjusted to provide the optimal desired response (eg, a therapeutic response). In certain embodiments, an antibody or antigen-binding fragment provided by the invention is administered to a subject once or in a series of treatments. In certain embodiments, an antibody or antigen-binding fragment provided by the invention is administered to a subject by one or more separate administrations or by continuous infusion, depending on the type and severity of the disease. For example, the relevant guidance can be found in U.S. Patents 4,657,760, 5,206,344, 5,225,212. The antibodies and antigen-binding fragments provided herein can be administered by any route known in the art, such as parenteral (eg, subcutaneous, intraperitoneal, intravenous (including intravenous infusion, intramuscular or intradermal injection) or Parenteral (eg, oral, intranasal, intraocular, sublingual, rectal or topical) routes. In certain embodiments, the antibodies and antigen-binding fragments provided herein are administered in a controlled release manner. Controlled-release parenteral formulations can be prepared as implants, oily injections or microparticle systems (eg, microspheres, microparticles, microcapsules, nanocapsules, nanospheres, and nanoparticles) (see, Banga, AJ, Therapeutic Peptides and Proteins: Formulation, Processing, and Delivery Systems, Technomic Publishing Company, Inc., Lancaster, Pa., (1995); Kreuter, J., Colloidal Drug Delivery Systems, J. Kreuter, ed., Marcel Dekker, Inc., New York, NY, pp. 219-342 (1994); Tice & Tabibi, Treatise on Controlled Drug Delivery, A. Kydonieus, ed., Marcel Dekker, Inc. New York, NY, pp. 315-339, (1992)). In certain embodiments, the antibodies and antigen-binding fragments disclosed herein can be administered in a degradable or non-degradable polymer matrix (see Langer, Accounts Chem. Res. 26:537-542, 1993). In certain embodiments, when a therapeutically effective amount of an antibody or antigen-binding fragment provided by the invention is administered to a subject, at least 10% (eg, at least 20%, at least 25%) is consumed in the subject At least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 99%) of IgA-expressing B cells. In certain embodiments, an antibody or antigen-binding fragment provided herein can be administered alone or in combination with one or more additional therapeutic agents or means. For example, an antibody or antigen-binding fragment provided by the present invention can be administered in combination with a second therapy or a second therapeutic agent for treating cancer, such as radiation therapy, chemotherapy, targeted therapy, gene therapy. , immunotherapy, hormonal therapy, angiogenesis inhibition, palliative treatment, cancer treatment surgery (eg, tumor resection) or one or more antiemetics or other treatments for complications caused by chemotherapy, the second therapeutic agent Such as: another antibody, therapeutic polynucleotide, chemotherapeutic agent, anti-angiogenic agent, cytokine, other cytotoxic agents, growth inhibitors. In certain of these embodiments, the antibodies or antigen-binding fragments provided herein can be administered concurrently with one or more additional therapeutic agents, and in certain embodiments of these embodiments, the antibodies or The antigen binding fragment and the additional therapeutic agent can be administered as part of the same pharmaceutical composition. However, an antibody or antigen-binding fragment administered in "combination" with another therapeutic agent need not be administered simultaneously with or in the same composition as the agent. An antibody or antigen-binding fragment thereof administered before or after another agent is considered to be "combined" with the agent, as used in the present invention, even if the antibody or antigen-binding fragment and the second agent are administered by different routes. Where possible, other therapeutic agents administered in combination with the antibodies or antigen-binding fragments provided by the present invention are based on the schedules listed in the product information sheets of the additional therapeutic agents or according to the Physicians' Desk Reference 2003 (Physicians' Desk Reference, Administration is performed by 57th Ed; Medical Economics Company; ISBN: 1563634457; 57th edition (November 2002)) or protocols well known in the art. C. Combination Therapy It may also be desirable to use the antibodies of the invention in combination with other anti-cancer therapies to provide combination therapies. These therapies will be provided in a combined amount effective to achieve a reduction in one or more disease parameters. The process involves simultaneously contacting the cells/subjects with two agents/therapies (eg, using a single composition or pharmacological formulation comprising both agents) or simultaneously by subjecting the cells/subjects to two different compositions Or the formulation is contacted, one of the compositions comprising the antibody and the other comprising the other agent. Alternatively, the antibody may be subjected to other treatments before or after an interval of minutes to weeks. One usually ensures that there is no long interval between each delivery time, so that the treatment can still produce a beneficial combined effect on the cells/subjects. In this case, it is contemplated that the cells can be contacted in two ways within about 12-24 hours of each other, within about 6-12 hours of each other, or within a delay of only about 12 hours. In some cases, it may be necessary to extend the treatment time; however, there are several days (2 days, 3 days, 4 days, 5 days, 6 days or 7 days) to several weeks between each application process (1) 2, 3, 4, 5, 6, 7 or 8 days). It is also contemplated that anti-mIgA antibodies or other therapies will be administered more than once. Various combinations can be employed in which the antibody is "A" and the other therapy is "B" as follows:Other combinations are also considered. In order to kill cells, inhibit cell growth, inhibit metastasis, inhibit angiogenesis, or otherwise reverse or reduce the malignant phenotype of tumor cells, the methods and compositions of the invention can be used to contact target cells or sites with antibodies and at least one other therapy. point. These therapies will be provided in a combined amount effective to kill or inhibit cancer cell proliferation. This process may involve the process of simultaneously contacting the cells/sites/subjects with the agent/therapy. In certain embodiments, the agent for combination therapy is selected from the group consisting of interleukin-2, clofarabine, farnesyl transferase inhibitor, decitabine, a platinum complex derivative, oxaliplatin, Kinase inhibitor, tyrosine kinase inhibitor, PI3 kinase inhibitor, BTK inhibitor, Ibrutinib, PD-1 antibody, PD-L1 antibody, CTLA-4 antibody, LAG3 antibody, ICOS antibody, TIGIT antibody, TIM3 An antibody, an antibody that binds to a tumor antigen, an antibody that binds to a T cell surface marker, an antibody that binds to a myeloid cell or an NK cell surface marker, an alkylating agent, a nitrosourea agent, an antimetabolite, an antitumor antibiotic , plant-derived alkaloids, topoisomerase inhibitors, hormone therapeutics, hormone antagonists, aromatase inhibitors, and P-glycoprotein inhibitors. D. Immunoassay Methods In certain embodiments, the invention provides immunodetection methods for preventing, detecting or diagnosing a cancer having an immunosuppressive microenvironment, the method comprising administering an antibody or antigen-binding fragment provided by the invention The biological sample contacts and determines the level of IgA or IgA-expressing cells in the biological sample from a subject suspected of having or having or at risk of developing cancer. Some immunoassay methods include enzyme-linked immunosorbent assay (ELISA), radioimmunoassay (RIA), immunoradiometric assay, fluorescent immunoassay, chemiluminescence assay, bioluminescence assay, and Western blotting. In particular, competitive assays for detecting and quantifying mIgA are also provided. The steps of various useful immunoassay methods are described in the scientific literature, for example, Doolittle and Ben-Zeev (1999), Gulbis and Galand (1993), De Jager et al. (1993) and Nakamura et al. (1987). Typically, immunological binding methods comprise: obtaining a sample suspected of containing a mIgA-associated cancer, and contacting the sample with a first antibody according to the invention under conditions effective to allow formation of an immune complex, as appropriate. These methods include methods for detecting or purifying cells expressing mIgA from a sample. Preferably, the antibody is linked to a solid support (eg, in the form of a column matrix) and a sample suspected of containing cells expressing mIgA is applied to the immobilized antibody. The undesired components are washed away from the column, the cells expressing mIgA are immunoconjugated to the immobilized antibody, and the immobilized antibody is collected by removing the organism or antigen from the column. The immunological binding method also includes a method for detecting and quantifying the number of cells or related components expressing mIgA in a sample, and detecting and quantifying any immune complex formed during the binding process. Here, a sample suspected of containing cells expressing mIgA will be obtained, and the sample is contacted with an antibody that binds to mIgA, and then the amount of the immune complex formed under specific conditions is detected and quantified. For antigen detection, the biological sample analyzed may be any sample suspected of containing mIgA expression, such as tissue sections or samples, homogenized tissue extracts, biological fluids (including blood and serum) or secretions (feces or urine). . The selected biological sample is contacted with the antibody under effective conditions for a period of time sufficient to allow formation of an immune complex (primary immune complex), which is typically by simply adding the antibody composition to the sample and incubating the mixture for a period of time. The problem is that the period of time is long enough for the antibody to form an immune complex, i.e., to bind the antibody to mIgA. After this, sample-antibody compositions (eg, tissue sections, ELISA plates, dot blots, or Western blots) are typically washed to remove any non-specifically bound antibody species, allowing only detection of specific binding in the primary immune complex. Those antibodies within. In general, detection of immune complex formation is well known in the art and can be accomplished by the application of a variety of methods. These methods are typically based on the detection of labels or labels, such as any radioactive, fluorescent, biological, and enzymatic labels. Patents relating to the use of such indicia include U.S. Patents 3,817,837, 3,850,752, 3,939,350, 3,996,345, 4,277,437, 4,275,149 and 4,366,241. Of course, other advantages can be found by using secondary binding ligands known in the art, such as binding arrangements for secondary antibodies and/or biotin/avidin ligands. The antibody used in the assay itself can be linked to a detectable label, wherein the label can be simply detected, thereby allowing determination of the amount of primary immune complex in the composition. Alternatively, the first antibody bound within the primary immune complex can be detected by a second binding ligand having binding affinity to the first antibody. In these cases, the second binding ligand can be attached to a detectable label. The second binding ligand itself is typically an antibody and thus may be referred to as a "secondary" antibody. The primary immune complex is contacted with the labeled secondary binding ligand or antibody under conditions effective for a period of time sufficient to allow formation of a secondary immune complex. The second immune complex is then typically washed to remove any non-specifically bound labeled secondary antibody or ligand and then the remaining label in the second immune complex is detected. Other methods include detecting the primary immune complex by a two-step process. As described above, a second binding ligand (eg, an antibody having an antibody with binding affinity) is used to form a secondary immune complex. After washing, the second immune complex is again contacted with a third binding ligand or antibody having binding affinity for the second antibody for a period of time sufficient to allow formation of an immune complex (tertiary immune complex) under effective conditions. The third ligand or antibody is linked to a detectable label to allow detection of the tertiary immune complex thus formed. The system provides signal amplification if needed. One immunoassay uses two different antibodies. The first biotinylated antibody is used to detect the target antigen, and then the second antibody is used to detect biotin linked to the complex biotin. In this method, the sample to be tested is first incubated in a solution containing the first step antibody. If a target antigen is present, some antibodies bind to the antigen to form a biotinylated antibody/antigen complex. The antibody/antigen complex is then amplified by incubation in a solution of streptavidin (or avidin), biotinylated DNA, and/or complementary biotinylated DNA, each step Additional biotin sites are added to the antibody/antigen complex. The amplification step is repeated until the appropriate level of amplification is reached, at which point the sample is incubated in a solution containing the second step antibody to biotin. The second step antibody is labeled, for example, using an enzyme that can detect the presence of an antibody/antigen complex by histone proteomics using a chromogen substrate. Macroscopically visible conjugates can be produced by suitable amplification. Another known immunoassay method utilizes an immuno-PCR (polymerase chain reaction) method. This PCR method is similar to the Cantor method until incubation with biotinylated DNA, but this method is not incubated with multiple rounds of streptavidin and biotinylated DNA, but with low pH or high salt buffer for antibody release. Wash off the DNA/biotin/streptavidin/antibody complex. The resulting wash solution is then used to carry out a PCR reaction with a suitable control and a suitable primer. At least in theory, the enormous amplification capacity and specificity of PCR can be used to detect a single antigen molecule. The antibodies of the invention may also be used in combination with fresh frozen and/or formalin-fixed paraffin-embedded tissue blocks prepared by immunohistochemistry (IHC). Methods for preparing tissue blocks from granular samples have been successfully used in IHC studies of various prognostic factors, and are well known to those skilled in the art (Brown et al, 1990; Abbondanzo et al, 1990; Allred et al, 1990). In still other embodiments, the invention relates to an immunoassay kit for use in the above immunoassay method. Since antibodies can be used to detect cells expressing mIgA, antibodies can be included in the kit. Thus, the immunoassay kit comprises a first antibody that binds to mIgA in a suitable container device, and optionally an immunodetection reagent. In certain embodiments, the antibody can be pre-bound to a solid support, such as a column matrix and/or a well of a microtiter plate. The immunodetection reagent of the kit can take any of a variety of forms including those detectable label forms associated with or linked to a given antibody. Detectable labels associated with or linked to secondary binding ligands are also contemplated. Exemplary second ligands are those having a binding affinity to the first antibody. Other suitable immunodetection reagents for use in the kits of the invention include bicomponent reagents comprising a second antibody having binding affinity to a first antibody, and a third antibody having binding affinity to a second antibody Wherein the third antibody is linked to a detectable label. As noted above, many exemplary labels are known in the art, and all of these labels can be used in conjunction with the present invention. The kit may also comprise a composition (whether labeled or unlabeled) of appropriately dispensed mIgA-expressing cells which can be used to prepare a standard curve for assay determination. The kit may contain the fully labeled form, the intermediate form or the antibody-labeled conjugate as a separate moiety to be conjugated by the user of the kit. The components of the kit can be packaged in an aqueous medium or in lyophilized form. The container means of the kit typically comprises at least one vial, test tube, flask, bottle, syringe or other container means in which the antibody can be placed, or preferably dispensed as appropriate. Kits of the invention will typically also include a reagent container for holding antibodies, antigens, and any other commercially available closures. Such containers may include injection or blow molded plastic containers in which the desired vials are retained.Example The following examples are provided to better illustrate the claimed invention and are not to be construed as limiting the scope of the invention. All of the specific compositions, materials and methods described below fall within the scope of the invention in whole or in part. These specific compositions, materials, and methods are not intended to limit the invention, but are merely illustrative of specific embodiments that fall within the scope of the invention. Equivalent compositions, materials, and methods can be developed by those skilled in the art without departing from the scope of the invention, without the ability to practice the invention. It should be understood that many variations can be made in the routines described herein while still remaining within the scope of the invention. It is the inventor's intention that such variations are included within the scope of the invention. Example 1: Construction and expression of recombinant mouse mIgA extracellular membrane-proximal domain (EMPD) fusion protein for immunization and serum/hybridoma screening To prepare mice for immunological knockout of IgA (IgA)^- /^- , Harriman et al., a mouse mIgA EMPD fusion protein (SEQ ID NO: 3) of rabbit or other immunocompetent animal, added a 10-fold his tag at the N-terminus of mouse CH2-CH3-mouse mIgA EMPD, and The C-terminal fusion leucine zipper (Figure 2). The expression cassette (SEQ ID NO: 3) was then cloned into GenScript's proprietary Lenti-puro mammalian expression vector (GenScript, Piscataway, NJ). Expression of the target gene is driven by the CMV promoter. The lentivirus construct was first amplified in HEK 293T cells and the viral particles were purified by ultracentrifugation of the supernatant of the lentivirus-infected 293T cell culture. The lentivirus carrying the expression cassette (SEQ ID NO: 3) was then used to infect CHO K1 cells to generate a stable cell bank. After selection under puromycin, the stable library was expanded to the desired volume and cultured according to the GenScript fed-batch protocol to express the mouse CH2-CH3-mouse mIgA EMPD fusion protein. After harvesting, the supernatant was clarified by filtration and then loaded onto a Nickle-NTA column for purification. The purified proteins were combined and desalted into PBS pH 7.2. To prepare a mouse mIgA EMPD fusion protein (SEQ ID NO: 4) for ELISA screening of immunized mouse sera, the mouse CH2-CH3 sequence (SEQ ID NO: 3) of the above mouse mIgA EMPD fusion protein was replaced with The human CH2-CH3 sequence (Fig. 3) was expressed and purified as described above for the SEQ ID NO:3 construct. Example 2: Construction and expression of recombinant human mIgA extracellular membrane-proximal domain (EMPD) fusion proteins for immunization and serum/hybridoma screening for preparation of mice for immunization (wild type or knockout of IgA) Rat, IgA^- /^- Or a rabbit or other immunocompetent animal human mIgA EMPD fusion protein (SEQ ID NO: 5), adding a 10xhis-tag at the N-terminus of mouse CH2-CH3-human mIgA EMPD 456S, and fused at the C-terminus The zipper (Figure 4), as well as expression and purification as described above, was used for the SEQ ID NO:3 construct. To prepare a human mIgA EMPD fusion protein (SEQ ID NO: 6) for ELISA screening of immunized mouse sera, the mouse CH2-CH3 sequence (SEQ ID NO: 5) of the above human mIgA EMPD fusion protein was replaced with human CH2. The -CH3 sequence, human mIgA EMPD long 456S was replaced with human mIgA EMPD short sequence (Figure 5) and expressed and purified as described above for the SEQ ID NO:3 construct. Example 3: Construction and expression of membrane-anchored mouse/human mIgA extracellular membrane-proximal domain (EMPD) for FACS binding assay and efficacy evaluation in order to prepare human IgA CH2-CH3 expressed on the cell surface Mouse mIgA EMPD fusion protein (SEQ ID NO: 7) was used for FACS binding assay, a flag tag was added at the N-terminus of human IgA CH2-CH3, and a cytoplasmic domain from mouse membrane IgA was fused at the C-terminus (CytoD And transmembrane domain (TMD) to generate human IgA CH2-CH3-mouse mIgA EMPD (Figure 6). To prepare a Flag-human IgA CH2-CH3-mα1S EMPD fusion protein (SEQ ID NO: 8) expressed on the cell surface for FACS binding assay, mouse mIgA EMPD from mouse membrane IgA as shown in Figure 6. , TMD and CytoD (SEQ ID NO: 7) were replaced with human IgA mα1S EMPD, TMD and CytoD (Figure 7). To prepare a Flag-human IgA CH2-CH3-mα1L 456S EMPD fusion protein (SEQ ID NO: 9) expressed on the cell surface for FACS binding assay, human IgA mα1S EMPD, TMD and CytoD as shown in Figure 7 (SEQ ID NO: 8) was replaced with human IgA mα1L 456S EMPD, TMD and CytoD (Figure 8). The gene encoding these fusion proteins was cloned into the pCDNA3.1 expression vector (Thermo Fisher Scientific, Waltham, MA) and transfected into HEK293 or CHO cells for expression of a transmembrane (or membrane-anchored) fusion protein, thereby For FACS based binding or screening assays. Example 4: Immunization and serum screening against anti-mouse mIgA specific titers A small Freund's adjuvant and 100 μg/mouse of mouse mIgA EMPD fusion protein (SEQ ID NO: 3) was used to immunize each knockout of IgA. Rat (IgA^- /^- ), then proceed to the immunization schedule shown in the table below. To screen anti-mouse mIgA-specific titers from immunized mouse sera, 100 μL/well of 96-well ELISA plates (Thermo Scientific Cat) using 1 ug/mL of antigen in 1x coating buffer (Biolegend Cat. No. 421701) #439454) Coating at 4 ° C overnight. The plates were washed 3 times with 200 μL of 1× Wash Buffer (Biolegend Cat #421601) per well. 200 μL of ELISA blocking buffer [PBS + 0.5% BSA (Cat# 001-000-162, Jackson Immuno Research) + 0.05% polysorbate 20] was added to the plate for 1 hour at room temperature. The plates were then washed 3 times with 200 uL of wash buffer per well. The mouse serum was diluted 100-fold with PBS as the highest concentration, and then serially diluted 10:3 (in triplicate) from the highest concentration at 1:3. Unimmunized mouse serum samples were diluted 100-fold with PBS, and 10 points were serially diluted 1:3 from the highest concentration for use as a negative control. Serially diluted non-immunized and immunized mouse sera were then added at 100 μL per well and incubated for 1 hour at room temperature. The plate was washed 6 times. 100uL HRP-F(ab’) diluted 1:10000₂ Goat anti-mouse IgG (H+L) (Jackson ImmunoResearch Cat #115-036-062) was added to the plates and incubated for 30 minutes at room temperature. The plate was washed 6 times. 100 μL of TMB one-component matrix (SurModics Cat#TM BW) was added to the plate, and the reaction was terminated by adding 100 μL of liquid stop solution (SurModics Cat #LBSP). Read the OD at 650 nm. Sera from #3 and #5 mice showed positive binding to human IgA CH2-CH3-mouse mIgA EMPD-leucine zipper (SEQ ID NO: 4) (Figure 9). Example 5: Mouse hybridoma fusion and screening Hybridoma fusion of mice immunized with mIgA was performed using cells from mIgA seropositive mice (#3 and #5 mice). Final blood collection and serum were also collected from these animals. ELISA titer analysis was performed using human IgA CH2-CH3-mouse mIgA leucine zipper protein (SEQ ID NO: 4, Figure 3). The ELISA results showed that the titer of #5 mice was slightly higher than that of #3 mice, which was approximately 1:10,000. A smaller amount of lymphocytes was recovered from these mice, and the amount recovered was 30-75 million cells/mouse. The spleen and lymph nodes are much smaller than other typical immunized mice. All lymphocytes are used in the fusion process. A total of 22 96-well plates (one T75 block) cultures were cultured and the secretion of anti-mouse mIgA antibodies was monitored. Example 6: Identification of antibodies that specifically bind to mouse mIgA In order to transiently express the N-terminal Flag-tagged human IgA CH2-CH3-mouse mIgA EMPD-TM fusion protein (SEQ ID NO: 7) on HEK293 cells, encoding The nucleic acid of the fusion protein was cloned into the pAC205 vector (Genscript, Piscataway, NJ) and transfected into HEK293 cells. Forty-eight hours after transfection, transfected HEK293 cells were harvested and used for FACS assessment of mouse mIgA expression. Serum samples from mIgA positive #3 mice were conjugated to transfected cells at 1:200 dilution (Figure 10), indicating that these mouse sera do contain antibodies that recognize membrane-bound mIgA. To generate a CHO stable cell line expressing the N-terminal Flag-tagged human IgA CH2-CH3-mouse mIgA EMPD-TM fusion protein (SEQ ID NO: 7), the nucleic acid encoding the fusion protein was cloned into the pAC226 stable expression vector (Genscript, Piscataway, NJ) was transfected into CHO cells. The puromycin was added to the transfected CHO cell culture medium (6 μg/ml) 48 hours after the transfection. Cells were harvested and used to FACS analysis after CHO cells were recovered from puromycin selection and reached 90% viability. The results obtained by FACS analysis using anti-Flag mAb and mIgA positive mouse (#3 mouse) serum indicated that membrane-bound mIgA was expressed on the surface of CHO cells (Fig. 11). Example 7: Immunization and identification of antibodies that specifically bind to human mIgA EMPD Wild-type or knock-out IgA mice were immunized with complete Freund's adjuvant and with 100 μg/mouse of human mIgA EMPD fusion protein (SEQ ID NO: 5). IgA^- /^- ), then proceed to the immunization schedule shown in the table below. Mouse mIgA EMPD (human mIgA EMPD fusion protein, SEQ ID NO: 6) was tested for titer binding 7 days after the last immunization. Human mIgA EMPD positive mice were sacrificed, and lymphocytes isolated from spleen and lymph nodes were used for hybridoma fusion. The fused hybridomas were seeded in 96-well plates and cultured. The cultured hybridoma supernatants were screened by ELISA for binding to human mIgA EMPD (SEQ ID NO: 6). ELISA positive wells were further screened by FACS for binding to human mIgA (SEQ ID NO: 8 and SEQ ID NO: 9) that bind to CHO cell membranes. FACS positive hybridomas (positive for both SEQ ID NO: 8 and SEQ ID NO: 9) were cloned and antibody heavy and light chain DNA sequences were obtained. These positive hybridoma clones were reformatted into mouse IgA2a and human IgGl for functional testing. Example 8: In vivo assay of anti-mouse mIgA antibody on mouse mIgA+ B cell depletion in tumor microenvironment and its effect on cancer treatment The mouse liver cancer model was fed with a high fat diet (MUP-uPA HFD feeding model). Urine protein-urokinase-type plasminogen promoter transgenic mice were used to test the effect of IgA-positive immunosuppressive B cell depletion on liver cancer progression. To establish this model, MUP-uPA mice were fed starting at 8 weeks of age (Nakagawa et al., Cancer Cell (2014) 162: 766-79). MUP-uPA HFD-fed mice have steatohepatitis with balloon-like degeneration, hepatocyte death, and pericellular/bridged fibrosis, which ultimately leads to spontaneously formed hepatocellular carcinoma (HCC) at 40 weeks of age. Consumption of mIgA+ B cells At 20 weeks of age, mice randomized and matched based on sex (male) and body weight were injected weekly with anti-mouse mIgA antibody (1-30 mg/kg). Mice that did not receive anti-mouse mIgA antibody were used as controls. At 40 weeks, the mice were sacrificed and the tumor volume was calculated as the width² ́ length/2. For multiple spontaneous liver tumors, the volume of a single tumor is added to obtain a total tumor volume. Results The tumor volume produced in MUP-uPA HFD-fed mice injected with anti-mouse mIgA antibody was significantly smaller than that of the control group, indicating that consumption of mIgA+ B cells inhibited liver cancer progression. Example 9: Induction of B cell apoptosis by anti-human mIgA antibody Ramos-hmIgA (human mIgA) cells were used to test the effect of anti-human mIgA antibodies on induction of human mIgA+ B cell lysis. Ramos cells (ATCC: Manassas, VA, #CRL-1596) are human Burkitt lymphoma cell lines. Ramos cells expressing human mIgA were generated by reverse transcriptional transfection of human membrane-anchored IgA (SEQ ID NO: 8 or 9). Incubation in culture medium (RPMI 1640, 10% FBS, 2 mM Gultamine) to a density of 0.2 ́10 by apoptosis assay⁶ /1.5 ml of cell lysis of Ramos-hmIgA cells. The background level of cell death in the assay was reduced by removing dead cells by ficoll gradient prior to the start of apoptosis assay. 0.2 ́10 in solution with and without anti-hmIgA antibody or control antibody⁶ The cells were cultured in triplicate for 72 hours. Cells were then harvested and analyzed for apoptosis using Annexin V-FITC Apoptosis Detection Kit I (BD Biosciences, San Jose, CA). The cells were washed twice in cold PBS and then resuspended in 100 μl of 1 ́ binding buffer (0.1 M Hepes/NaOH (pH 7.4), 1.4 M NaCl, 25 mM CaCl).₂ )in. The cells were then stained in the dark with 2.5 ul of annexin V-FITC antibody and 5 ul of propidium iodide (PI). After 15 minutes, 400 μl of 1 ́ binding buffer was added to each tube, and the cells were analyzed on a FACS machine. Each sample collects approximately 10-20,000 events. For annexin-V and PI, dead cells were positive. The FlowJo FAC analysis software (Tree Star, Inc., Ashland, OR) was used to calculate the percentage of each dead and dying population. The triplicate data is the calculated mean and standard deviation. The percentage of apoptosis was calculated as the sum of dead and dying cells and plotted using Excel. Anti-IgM antibodies (Kaptein, J. et al; JBC (1996) Vol. 271, No: 31, 18875-18884) were used as positive controls for inducing apoptosis in the Ramos-hmIgA cell line. An anti-pg120 mIgGl antibody was used as a negative control. Anti-human IgA antibodies were also used for comparison. Our results show that anti-gp120 antibodies do not induce apoptosis on untreated cells. Anti-hmIgA antibodies induce apoptosis in Ramos-hmIgA cells. Example 10: Induction of ADCC by anti-human mIgA antibody Antibody-dependent cell-mediated toxicity enables cytotoxic cells to bind (by antibodies) antigen to target cells, and subsequently kill the target cells with cytotoxin. Anti-mIgA antibodies with ADCC activity or enhanced ADCC activity may have enhanced therapeutic value in the treatment of IgA mediated disorders. Antibodies produced in non-fucosylated mammalian cells have been found to have enhanced ADCC activity. The following experiments describe the use of fucosylated and nonfucosylated anti-hmIgA antibodies. NK cells were isolated from 100 ml whole blood (Stem Cell Technologies). The purity of NK cells was determined by anti-human CD56 staining. Use >70% pure CD56 in each assay⁺ NK cells. Anti-hmIgA antibodies and HERCEPTIN® anti-Her2 MAb huIgG1 isotype controls were serially titrated. These antibodies (50 μl) were incubated with Ramos cells overexpressing human mIgA on the cell surface (cell line formation see Example 9) for 30 minutes at room temperature in RPMI-1640 (phenol red free) containing 1% FBS. . NK cells (50 μl) were then added to the cell line in a 15:1 ratio (150,000 NK cells to 10,000 targets (Ramos-hmIgA)). The measurements were performed in triplicate. Ramos-hmIgA, antibodies and NK cells were then incubated for 4 hours at 37 °C. After the cultivation, the 96-well U-bottom plate was rotated and the supernatant (100 μl) was harvested. The LDH release of the supernatant was then tested using the LDH reaction assay (Roche). Percent cytotoxicity was calculated for both target and lysed targets. The bactericide and LDH reaction mixture were incubated in an equal volume for 30-60 minutes as described by the manufacturer. The plate was then read at 490 nm. The percent cytotoxicity (%) was calculated as follows: (Exp value - target only) / lysed target - target only). Use Kaleidagraph to plot the data and use the best fit curve to generate the ED50 value. Our results show that the HERCEPTIN® huIgG1 isotype control antibody induces low levels of cytotoxicity. Anti-hmIgA antibodies induce specific cytotoxicity. The fucosylated and nonfucosylated forms of the anti-hmIgA antibody induced a similar maximum percentage (%) of cytotoxicity (about 70-80%). Based on EC50, non-fucosylated anti-hmIgA antibodies are more potent than fucosylated forms. Example 11: Transgenic mice with human EMPD domain Similar to the human IgA1 or IgA2 locus, the mouse IgA locus also encodes an alternative exon that results in secreted IgA or membrane IgA. To validate human EMPD as a potential target for antibodies against human membrane IgA, we generated mice with a "knock-in" human EMPD domain in the mouse IgA locus. This knock-in is allowed in IgA⁺ Mouse IgA with human EMPD domain was expressed on the surface of B cells (Fig. 12, see also Harriman et al, J Immunol (1999) 162: 2521-29; Mcpherson et al, Mucosal Immunology (2008) 1: 11-22; Wood et al, EMBO Journal (1983) 2(6)). The EMPD sequence is expressed on membrane-anchored IgA but not on secreted IgA. Specificity was used for the mouse IgA locus (P1 and P4, Figure 12) and human EMPD sequences (P2 and P3, Figure 12) or a combination thereof (mouse P1 and human P2; human P3 and mouse P4) Primers were used to genotype mice knocked into human EMPD by PCR. Purified genomic DNA was extracted with the above primers using the following procedure of 32 loops [4 minutes at 94 ° C; 1 minute at 94 ° C; 30 seconds at 60 ° C; 1 minute (30 loops at 72 ° C); 10 minutes at 72 ° C) analysis. The PCR product was electrophoresed on a 2% agarose 0.5 x TBE gel. The expected PCR products (or lack thereof) and their length well identify the targeting of knock-in human EMPD at the mouse IgA locus for replacement of mouse EMPD. ES cells knocked into human EMPD and final mouse strains were screened and verified by Southern blotting. The overnight 10 μg of purified ES cells or mouse tail genomic DNA was digested with an appropriate endonuclease. The digested DNA was electrophoresed on a 0.8% agarose 1 x TAE gel. The DNA was then transferred to a nylon membrane (Roche) using denaturing buffer (1.5 M NaCl; 0.5 M NaOH) overnight. The membrane was rinsed, UV crosslinked, then immersed in DIG Easy Hyb solution (Roche) for 4 hours and rotated at 46 °C. Probes were generated by PCR using the PCR DIG Probe Synthesis Kit according to the manufacturer's instructions (Roche). The nucleic acid sequence encoding human EMPD fragment GGCTCTTGCTCTGTTGCAGATTGGCAGATGCCGCCTCCCTATGTGGTGCTGGACTTGCCGCAGGAGACCCTGGAGGAGGAGACCCCCGGCGCCAAC (SEQ ID NO: 10) was used for Southern blot analysis. Probes were tested against unlabeled PCR products to ensure increased size and good DIG labeling. The blot was then spun overnight at 46 °C with a boiled probe overnight. The next day blot was then washed and stained with anti-DIG antibody according to the manufacturer's instructions. The blot was exposed to the membrane for 15-20 minutes. Example 12: Anti-mouse mIgA antibody against human mIgA in tumor microenvironment⁺ In vivo assay of B cell depletion and its effect on the regulation of cancer treatment Mouse liver cancer model Human mIgA transgenic mice (see Example 11) were crossed with MUP-uPA mice to generate MUP-uPA-hmIgA mice, which mice It was used to test the effect of human mIgA B cell depletion on the progression of liver cancer. To establish a liver cancer model, HFD was fed MUP-uPA-hmIgA mice starting at 8 weeks of age. MUP-uPA-hmIgA HFD-fed mice have steatohepatitis with balloon-like degeneration, hepatocyte death, and pericellular/bridged fibrosis, which ultimately leads to spontaneously formed hepatocellular carcinoma (HCC) at 40 weeks of age. Consumption of mIgA+ B cells At 20 weeks of age, mice randomized and matched based on sex (male) and body weight were injected weekly with anti-mouse mIgA antibody (1-30 mg/kg). Mice that did not receive anti-mouse mIgA antibody injections were used as controls. At 40 weeks, the mice were sacrificed and the tumor volume was calculated as the width² ́ length/2. For multiple spontaneous liver tumors, the volume of a single tumor is added to obtain a total tumor volume. Results The tumor volume produced in MUP-uPA-hmIgA HFD-fed mice injected with anti-mouse mIgA antibody was significantly smaller than that of the control group, indicating depletion of human mIgA.⁺ B cells inhibit the progression of liver cancer. Although the present invention has been particularly shown and described with reference to the preferred embodiments of the present invention, those skilled in the art should understand There are various changes in form and detail.

以下附圖為本說明書的一部分，並且用來進一步說明本發明的某些方面。通過參考其中一個或多個附圖並結合本發明給出的具體實施方式的詳細描述，可以更好地理解本發明。圖 1 示出了在人IgA1（分泌物α1）的C-末端和CH3結構域與人IgA 1的膜錨定肽（mα1）的連接處的基因區段的核苷酸序列及其編碼的氨基酸序列。膜IgA含有三個其他的C末端結構域，即細胞外膜近端結構域（EMPD）、跨膜結構域（TMD，底線部分）和細胞質結構域（CytoD）。在膜外顯子中使用兩個可選的剪接受體位點導致EMPD長度上產生6個氨基酸差異，一個長（α1L）EMPD和一個短（α1S）EMPD。存在於α1L同種型中但不存在於α1S同種型中的6個氨基酸殘基的額外區段，GSCSVA，用方框標出。另一個等位基因在方框內的第4個氨基酸處用C替代S，產生GSCCVA。星號表示終止密碼子。分泌物α1（殘基1-472）中氨基酸序列的編號與Liu等人(1976)發表的相同。對於α1和mα1（殘基1-452）共有的部分，mα1的氨基酸序列編號採用α1的編號。對於mα1L同種型，殘基453-523，編號繼續不間斷。對於mα1S同種型，GSCSVA區段，殘基453-458不存在。在臺灣人群中，除了已知的mα1等位基因外，其中上述6個氨基酸區段中的第4個氨基酸殘基是S（SEQ ID NO:1），mα1也具有等位基因，其中第4個氨基酸殘基是C（SEQ ID NO:2）。圖 2 示出了用於抗小鼠mIgA EMPD免疫的10xhis-小鼠IgA CH2-CH3-小鼠-mIgA EMPD-亮氨酸拉鍊的融合蛋白。圖 3 示出了通過ELISA篩選的用於抗小鼠mIgA EMPD的10xhis-人IgA CH2-CH3-小鼠-mIgA EMPD-亮氨酸拉鍊的融合蛋白。圖 4 示出了用於抗人mIgA EMPD免疫的10xhis-小鼠IgA CH2-CH3-人-mIgA EMPD長456S-亮氨酸拉鍊的融合蛋白。圖 5 示出了通過ELISA篩選的用於抗人mIgA EMPD的10xhis-人IgA CH2-CH3-人-mIgA EMPD短-亮氨酸拉鍊的融合蛋白。圖 6 示出了通過FACS篩選的用於抗人mIgA EMPD的標籤-人IgA CH2-CH3-小鼠-mIgA EMPD-TM的融合蛋白。圖 7 示出了用於Ramos細胞表面表達的標籤-人IgA CH2-CH3-人mIgA EMPD 短-TM-CytoD的融合蛋白。圖 8 示出了標籤-人IgA CH2-CH3-人mIgA EMPD長456S-TM-CytoD的融合蛋白。圖 9 示出了在塗覆有人IgA CH2-CH3-小鼠mIgA EMPD亮氨酸拉鍊蛋白（SEQ ID NO：4）平板上對mRgA小鼠的血清滴度分析。圖 10 示出了使用用標籤-人IgA CH2-CH3-小鼠mIgA-TM（SEQ ID NO：7）轉染的HEK293FACS篩選ELISA陽性孔。圖 11 示出了與表達標籤-人IgA CH2-CH3小鼠mIgA-TM（SEQ ID NO：7）的CHO穩定庫結合的3號小鼠血清。圖 12 示出了用人EMPD敲入小鼠產生小鼠膜結合的IgA的示意圖。The following drawings are part of the specification and are used to further illustrate certain aspects of the invention. The invention may be better understood by reference to the Detailed Description of the Detailed Description of the invention. Figure 1 shows the nucleotide sequence of the gene segment at the junction of the C-terminus of human IgA1 (secretion α1) and the membrane anchor peptide (mα1) of human IgA 1 and its encoded amino acid sequence. Membrane IgA contains three other C-terminal domains, the outer membrane proximal domain (EMPD), the transmembrane domain (TMD, the bottom line portion), and the cytoplasmic domain (CytoD). The use of two alternative splice acceptor sites in the membrane exon resulted in a 6 amino acid difference in length of EMPD, one long (α1L) EMPD and one short (α1S) EMPD. An additional segment of 6 amino acid residues present in the α1L isoform but not present in the α1S isoform, GSCSVA, is indicated by a box. Another allele replaces S with C at the 4th amino acid in the box to produce GSCCVA. The asterisk indicates the stop codon. The numbering of the amino acid sequence in the secretion α1 (residue 1-472) is the same as that published by Liu et al. (1976). For the portion shared by α1 and mα1 (residue 1-452), the amino acid sequence number of mα1 is numbered by α1. For the mα1L isoform, residues 453-523, the numbering continues uninterrupted. For the mα1S isoform, the GSCSVA segment, residues 453-458 are not present. In the Taiwanese population, in addition to the known mα1 allele, the fourth amino acid residue in the above six amino acid segments is S (SEQ ID NO: 1), and mα1 also has an allele, of which 4 The amino acid residue is C (SEQ ID NO: 2). Figure 2 shows a fusion protein of 10xhis-mouse IgA CH2-CH3-mouse-mIgA EMPD-leucine zipper for anti-mouse mIgA EMPD immunization. Figure 3 shows a fusion protein of 10xhis-human IgA CH2-CH3-mouse-mIgA EMPD-leucine zipper for anti-mouse mIgA EMPD screened by ELISA. Figure 4 shows a fusion protein of 10xhis-mouse IgA CH2-CH3-human-mIgA EMPD long 456S-leucine zipper for anti-human mIgA EMPD immunization. Figure 5 shows a fusion protein of 10xhis-human IgA CH2-CH3-human-mIgA EMPD short-leucine zipper for anti-human mIgA EMPD screened by ELISA. Figure 6 shows a fusion protein for the anti-human mIgA EMPD tag-human IgA CH2-CH3-mouse-mIgA EMPD-TM screened by FACS. Figure 7 shows a fusion protein for the tag-human IgA CH2-CH3-human mIgA EMPD short-TM-CytoD for surface expression of Ramos cells. Figure 8 shows the fusion protein of the tag-human IgA CH2-CH3-human mIgA EMPD long 456S-TM-CytoD. Figure 9 shows serum titer analysis of mRgA mice on plates coated with human IgA CH2-CH3-mouse mIgA EMPD leucine zipper protein (SEQ ID NO: 4). Figure 10 shows the screening of ELISA positive wells using HEK293 FACS transfected with the tag-human IgA CH2-CH3-mouse mIgA-TM (SEQ ID NO: 7). Figure 11 shows mouse No. 3 serum bound to the CHO stable library expressing the tag-human IgA CH2-CH3 mouse mIgA-TM (SEQ ID NO: 7). Figure 12 shows a schematic representation of mouse membrane-bound IgA produced by human EMPD knock-in mice.

Claims

A method for treating an immunoglobulin A (IgA)-related disease in a subject, the method comprising administering to the subject a therapeutically effective amount of an antibody or antigen-binding fragment thereof that specifically binds to membrane IgA, thereby The IgA-expressing cells are eliminated or reduced in the subject or the activation or immunosuppressive function of IgA-expressing B cells is blocked.

The method of claim 1, wherein the antibody specifically binds to the extracellular membrane proximal domain (EMPD) of IgA.

The method of claim 1, wherein the antibody specifically binds to an epitope in the EMPD of human IgA1.

The method of claim 1, wherein the antibody specifically binds to an epitope in the EMPD of human IgA2.

The method of claim 1, wherein the antibody specifically binds to an epitope in the EMPD of IgA1 and the EMPD of IgA2.

The method of claim 1, wherein the antibody specifically binds to a peptide comprising the sequence of SEQ ID NO: 1 or SEQ ID NO: 2.

The method of claim 1, wherein at least 50% of the IgA-expressing B cells are eliminated in the subject.

The method of claim 1, wherein the IgA-related disease is cancer.

The method of claim 8, wherein the cancer is prostate cancer, hepatocellular carcinoma or hepatocellular cancer (HCC).

The method of claim 1, wherein the IgA-related disease is IgA nephropathy, Henoch-Schonlein purpura, or celiac disease.

The method of claim 1, wherein the antibody or fragment thereof is F(ab)'2, Fab, Fv or a single-chain Fv fragment.

The method of claim 1, wherein the antibody is a chimeric, humanized or human antibody.

The method of claim 1, wherein the antibody or fragment thereof is administered in combination with CAR-T or other cell therapy.

The method of claim 1, further comprising administering to the subject one or more drugs selected from the group consisting of platinum complex derivatives, oxaliplatin, tyrosine kinase inhibitors, and PI3 kinase inhibition. Agent, BTK inhibitor, Ibrutinib, PD-1 antibody, PD-L1 antibody, CTLA-4 antibody, LAG3 antibody, ICOS antibody, TIGIT antibody, TIM3 antibody, antibody binding to tumor antigen, and T cell surface marker Antibody, antibody binding to myeloid or NK cell surface markers, alkylating agent, nitrosourea, antimetabolite, antitumor antibiotic, plant-derived alkaloid, topoisomerase inhibitor Hormone therapeutics, hormone antagonists, aromatase inhibitors, and P-glycoprotein inhibitors.

A method for preventing, detecting or diagnosing cancer in a subject having an immunosuppressive microenvironment, the method comprising: (i) obtaining a sample from a subject suspected of having or having or at risk of developing cancer (ii) contacting the antibody or antigen-binding fragment thereof that specifically binds to membrane IgA with the biological sample; (iii) determining the level of IgA or expressing IgA cells in the biological sample; and (iv) determining the IgA or The level of cells expressing IgA was compared to the reference level of IgA or IgA-expressing cells.

The method of claim 15, wherein the cancer is prostate cancer, hepatocellular carcinoma or hepatocellular cancer (HCC).

The method of claim 15, wherein the sample is a blood sample or a tumor biopsy.

The method of claim 15, wherein the subject is treated with or has been treated with one or more drugs selected from the group consisting of platinum complex derivatives, oxaliplatin, tyrosine kinase inhibitors, PI3 kinase inhibitor, BTK inhibitor, Ibrutinib, PD-1 antibody, PD-L1 antibody, CTLA-4 antibody, LAG3 antibody, ICOS antibody, TIGIT antibody, TIM3 antibody, antibody binding to tumor antigen, and T Cell surface marker-bound antibody, antibody binding to myeloid or NK cell surface marker, alkylating agent, nitrosourea, antimetabolite, antitumor antibiotic, plant-derived alkaloid, topological isomerism Enzyme inhibitors, hormone therapeutics, hormone antagonists, aromatase inhibitors, and P-glycoprotein inhibitors.

The method of claim 15, wherein the reference level of the IgA or IgA-expressing cells is from a healthy subject or an adjacent healthy tissue.

The method of claim 15, further comprising administering to the subject a therapeutically effective amount of the antibody or antigen-binding fragment thereof that specifically binds to membrane IgA.

A transgenic animal expressing human membrane-anchored IgA.

The transgenic animal of claim 21, which is a mouse.

The transgenic animal of claim 21, which is a mouse that knocks out the mouse endogenous IgA gene (IgA-/-).

The transgenic animal of claim 21, wherein the human IgA gene is knocked in at the endogenous mouse IgA locus.

The transgenic animal of claim 21, wherein the human EMPD segment of the membrane IgA replaces mouse EMPD of mouse IgA.

The transgenic animal of claim 21, wherein the human IgA is expressed on the surface of IgA positive B cells.

The transgenic animal of claim 21, wherein the human EMPD is expressed on the surface of IgA positive B cells.