JP2007159874A - Ligand immobilization substrate and cell selective adsorbent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a porous film type ligand immobilization substrate having epoxy group as a functional group for immobilization and preventing the lowering of affinity property after the ligand immobilization by designing a chemical structure on the substrate surface when creating a cell selective adsorbent by immobilizing the affinity ligand, and its production method; and to provide the cell selective adsorbent exerting superior selective adsorbent property of a target cell by immobilizing the affinity ligand on the ligand immobilization substrate, and its production method. <P>SOLUTION: This ligand immobilization substrate wherein a specific chemical structure group containing epoxy group at least on the surface section of a porous film, is used as the cell selective adsorbent by immobilizing the ligand having the affinity on the specific cell surface, and its production method is provided. The cell selective adsorbent is formed by immobilizing the ligand having the affinity on the specific surface, on the ligand immobilization substrate; and its production method is provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cell selective adsorbent used for selectively adsorbing, removing or recovering target cells from a cell suspension such as blood with an affinity ligand fixed to the adsorbent, and a method for producing the same. Furthermore, when the present invention is used for preparing a cell selective adsorbent by immobilizing a peptide type affinity ligand, the ligand performance is effectively expressed without losing the original affinity of the ligand even after the ligand is immobilized. The present invention relates to a ligand-immobilizing substrate and a method for producing the same.

In recent years, “leukocyte removal therapy” that removes leukocyte cells (mainly lymphocytes and granulocytes) from the blood of patients has been used to treat autoimmune diseases such as ulcerative colitis and rheumatism. . In this treatment method, let's control the immune function by passing the patient's blood through a column packed with a water-insoluble adsorbent that can adsorb leukocyte cells non-selectively and adsorbing and removing leukocyte cells in the blood. It is a kind of blood extracorporeal circulation method.
However, since such leukocyte removal therapy is intended to non-selectively remove all leukocyte cells responsible for immune function, there is a concern that the patient's immune function will be reduced more than necessary, Recently, a movement to selectively remove only cells that are considered to have a particularly large effect in each disease has been activated.

  For example, there are two types of helper T cells which are CD4 positive cells (cells having CD4 antigen as a marker on the cell surface) and suppressor T cells which are CD8 positive cells, which are mainly involved in regulating the immune response. In a normal person, these CD4 positive cells and CD8 positive cells exist in a well-balanced manner, so that the immune response in the living body is maintained in an appropriate state. However, for some reason, if there is a large fluctuation in the number ratio between the two in the blood, there is a report that abnormalities occur in the immune system control system in the living body and various adverse effects on the human body. Recently, based on these facts, cell-adsorbing materials for selectively adsorbing and removing CD4-positive cells from blood have been developed.

In the field of regenerative medicine, hematopoietic stem cell transplantation therapy is used not only for the treatment of conventional acute myeloid leukemia and aplastic anemia, but also for the most severe peripheral arterial occlusive diseases (Burger disease, obstructive arteriosclerosis, diabetic). As a new method, various techniques for securing a sufficient amount of hematopoietic stem cells have been actively developed. Cell adsorbents that selectively adsorb and collect CD34 positive cells from the patient's own peripheral blood have also been developed.
In addition, technical disclosures regarding the development of selective cell adsorbents targeting activated macrophages, activated leukocytes, inflammatory leukocytes, tumor cells, cancer cells, etc. have been made, and not only blood but also various cell suspensions It is considered that the development of selective cell adsorbents targeting various cells from the future will continue to be active (see, for example, Patent Document 1).
In general, beads and fibers are often used as the shape of the adsorption substrate used for the cell adsorbent.

As a method for imparting selective cell adsorption performance to the adsorption substrate, cationic functional groups (for example, primary amino group, secondary amino group, tertiary amino group, quaternary ammonium group) or anionic property on the substrate surface A technique for selectively adsorbing cells by immobilizing functional groups (for example, sulfate ester group, sulfonic acid group, carboxyl group, phosphate ester group) in a well-balanced manner has been conventionally known. In many cases, it is difficult to express high cell selectivity.
On the other hand, in order to obtain a high cell selective adsorption property, an affinity ligand having a specific affinity for a protein and / or sugar chain present on the cell surface of the target cell and immobilizing it on a substrate is It is effective. In particular, antibodies having an amino acid sequence that expresses a strong affinity for cell surface proteins and / or sugar chains, antibody fragments (F (ab) ′, Fab, Fab ′, etc.) containing antigen binding sites of antibodies, A synthetic peptide having such an amino acid sequence or a modified peptide thereof is effective, and a method of immobilizing them on an adsorption substrate by a covalent bond is considered preferable. Furthermore, when producing a cell-selective adsorbent that selectively removes or collects cells from blood, it is preferable that the safety of the ligand is high, specifically the antigenicity of the ligand is low. It can be said that a peptide-type ligand having a relatively small molecular weight is preferable.

When immobilizing peptide-type ligands on an adsorbent substrate such as a nonwoven fabric, the peptide is immobilized on the substrate by covalent bonding using functional groups, such as amino groups, carboxyl groups, and hydroxyl groups, at the molecular chain ends and amino acid residues. Is convenient. Therefore, the adsorbing substrate only needs to have at least a functional group that reacts with an amino group, a carboxyl group, a hydroxyl group, or the like on the surface.
However, when an antibody or peptide-type ligand is immobilized on an adsorption substrate to create a cell selective adsorbent, the affinity expression site in the ligand molecule (ie, the antigen binding site) may be localized at a specific site in the ligand molecule. In general, depending on the immobilization method, the affinity expression site of the ligand may be crushed and the cell selective adsorption function may not be expressed at all. In particular, relatively small ligands such as peptides are immobilized. Such a phenomenon is likely to occur. That is, simply having a large number of functional groups that can be used for immobilizing peptide ligands on a substrate nonwoven fabric is not sufficient as a substrate for immobilizing ligands, and after immobilizing peptide ligands on such substrates, It is necessary to use a ligand-immobilizing substrate that is devised so as not to cause a decrease in ligand affinity (in other words, a decrease in the adsorption rate of target cells).

As a selective cell adsorbent based on a nonwoven fabric, for example, Patent Document 2 discloses that the surface has the formula: —CO— (CH ₂ ) n—X (X is any atom of Cl, Br, I, n is A peptide having an affinity for the CD4 protein or a modified peptide thereof is immobilized on a non-woven fabric having an average fiber diameter of 1 to 30 μm, into which a functional group as shown in FIG. CD4 positive cell collecting material to be used, and in Patent Document 3, a peptide having affinity for CD4 protein or a modified peptide thereof is immobilized on a non-woven fabric having an epoxy group on the surface and an average fiber diameter of 1 to 30 μm. A CD4-positive cell trapping material characterized by the above is disclosed. Certainly, such functional groups can immobilize peptide-type ligands, but the chemical surface design of the base material including these functional groups has not been specifically devised. There is a possibility that it may not be sufficient as a base material for use.

In particular, epoxy groups are relatively easy to introduce into polyolefin-based nonwoven fabrics and cellulose-based nonwoven fabrics, and can be covalently bonded to functional groups (mainly amino groups) of peptide residues. Since conversion into various functional groups is also possible, it is considered that a nonwoven fabric-type ligand immobilization base material on which an epoxy group is immobilized is very effective for producing a cell selective adsorbent. However, as described in Patent Document 3, glycidyl methacrylate or a derivative thereof (having 2 to 5 methylene groups connecting an epoxy group and an ester group) is irradiated with a nonwoven fabric (for example, polyethylene or Polypropylene nonwoven fabric) with epoxy group introduced by immobilization method, when antibody (immunoglobulin, molecular weight is about 150 kDa) is immobilized on this, the original high affinity of the antibody is expressed without any problem. In many cases, it is possible to obtain a cell-selective adsorbent that sufficiently captures cells, but strangely, when Fab ′ having a molecular weight of about 50 kDa, which is an antibody fragment having the antigen-binding site, is used as a ligand, the affinity function can be obtained. In many cases, the target cell is greatly reduced and the target cell can hardly be removed.
In other words, when a cell selective adsorbent is produced using a peptide having a relatively small molecular weight, which is preferable in terms of ligand safety and ligand production cost, as a ligand for the cell selective adsorbent, the inherent affinity after ligand immobilization is lost. It is preferable to use a substrate for immobilizing a ligand in which the chemical structure of the surface of the nonwoven fabric containing epoxy groups is designed in advance so as not to be damaged. Such a substrate for immobilizing a ligand and cell selection using the same Development of adsorbents is desired.

On the other hand, as the chemical surface design of the base material including the epoxy group has been devised, Patent Document 4 discloses that the styrene-glycidyl methacrylate polymer has a physiological activity via a spacer (particularly an ethylene glycol diglycidyl ether derivative). Microspheres to which the substance is bound, and substances that can be attached to the physiologically active substance using the microsphere, such as a specific protein, are mixed in the mixture containing the substance (for example, after disruption of the cell membrane, A method for separating from a cell extract obtained through a treatment step is disclosed. However, it is not known at all whether such microspheres exhibit excellent performance as an adsorbent for specific cells, and neither Patent Document 4 suggests nor teaches such a concept. Naturally, the capture capacity required is different for normal proteins and cells because they differ by about 100 to 1000 times in size. Therefore, the adsorbent must be designed according to the object, including the shape of the adsorbent substrate. Don't be.
JP 2000-217909 A Japanese Patent Laid-Open No. 06-269663 Japanese Patent Laid-Open No. 06-218051 Japanese Patent Laid-Open No. 10-195099

  In the present invention, when an affinity ligand such as a peptide-type ligand is immobilized to prepare a cell selective adsorbent, the chemical structure of the substrate surface is designed so that the original affinity does not decrease even after the ligand is immobilized. It is another object of the present invention to provide a porous membrane type ligand immobilization base material having an epoxy group as an immobilization functional group and a method for producing the same. Furthermore, the present invention expresses excellent selective adsorption performance of target cells by immobilizing an affinity ligand such as a peptide-type ligand on the ligand-immobilizing substrate of the present invention, and is also excellent in safety and cost performance. Another object is to provide a porous membrane type cell selective adsorbent and a method for producing the same.

［ここで式（１）中のＲ^１は、Ｈ、炭素数１〜５のアルキル基、炭素数１〜５のアルキル基が有する１つ以上の水素原子をＯＨ基で置換した化学構造基、および下記式（２）で示される化学構造基から選ばれ、式（１）および式（２）のｎは１〜４の整数である。］

２）式（１）で示される化学構造基をＺとする時、Ｚの多孔膜の表面での結合が、膜成分であるアクリル酸エステルまたはメタクリル酸エステル系重合体に含まれる式（３）で示されるモノマーユニット構造の一部としての結合である、上記１）に記載のリガンド固定化用基材。

［ここで式（３）中のＲ^２はＨまたはＣＨ_３である］
３）リガンド固定化用基材１ｇに含まれるエポキシ基の含有量が１〜５００（μｍｏｌ／ｇ）であり、同じく窒素原子の含有量が１０〜２０００（μｍｏｌ／ｇ）であることを特徴とする上記１）又は２）に記載のリガンド固定化用基材。
４）多孔膜が、平均繊維径０．１μｍ〜５０μｍの不織布であることを特徴とする上記１）〜３）のいずれかに記載のリガンド固定化用基材。
５）上記１）〜４）のいずれかに記載のリガンド固定化用基材に、特定の細胞表面に親和性を有するアフィニティーリガンドの少なくとも１種を固定化したことを特徴とする細胞選択吸着材。
６）特定の細胞がＣＤ４陽性細胞である上記５）に記載の細胞選択吸着材。
７）アフィニティーリガンドがペプチド型リガンドであることを特徴とする上記５）又は６）に記載の細胞選択吸着材。
８）ペプチド型リガンドの分子量が０．５〜１３０ｋＤａである上記７）に記載の細胞選択吸着材。
９）多孔膜の少なくとも表面部分に化学的に結合されたエポキシ基にアンモニアおよび／または１級アミン化合物を反応させる工程、および該工程によって生成する１級アミノ基および／または２級アミノ基を少なくとも表面部分に有する多孔膜にジグリシジル化合物の少なくとも１種を反応させる工程を含むことを特徴とするリガンド固定化用基材の製造方法。
１０）ジグリシジル化合物が、式（４）で示される化学構造から選ばれることを特徴とする上記９）に記載のリガンド固定化用基材の製造方法。

［ここで式（４）のｎは１〜４の整数である。］
１１）多孔膜の少なくとも表面部分に化学的に結合されたエポキシ基が、エポキシ基を有する重合性モノマーを少なくとも用いた放射線照射グラフト重合法によって得られた重合体に由来するものであることを特徴とする上記９）または１０）に記載のリガンド固定化用基材の製造方法。
１２）上記５）〜８）のいずれかに記載の細胞選択吸着材を充填してなることを特徴とする細胞選択吸着カラム。
１３）上記１２）に記載の細胞選択吸着カラムを用いて細胞浮遊液中のターゲット細胞を吸着する方法。 As a result of intensive studies to achieve the above object, the present inventors have completed the present invention.
That is, the present invention is as follows.
1) A substrate for immobilizing a ligand, characterized in that at least one chemical structural group represented by the formula (1) containing an epoxy group and a nitrogen atom is chemically bonded to at least a surface portion of the porous membrane. .

[Wherein R ¹ in formula (1) is a chemical structural group obtained by substituting one or more hydrogen atoms of H, an alkyl group having 1 to 5 carbon atoms, or an alkyl group having 1 to 5 carbon atoms with an OH group, And selected from chemical structural groups represented by the following formula (2), n in the formulas (1) and (2) is an integer of 1 to 4. ]

2) When the chemical structural group represented by the formula (1) is Z, the formula (3) in which the bond on the surface of the porous film of Z is contained in the acrylate ester or methacrylate ester polymer as the membrane component The substrate for immobilizing a ligand according to 1) above, which is a bond as a part of a monomer unit structure represented by

[Wherein R ² in the formula (3) is H or CH ₃ ]
3) The content of epoxy groups contained in 1 g of the ligand immobilizing substrate is 1 to 500 (μmol / g), and the content of nitrogen atoms is also 10 to 2000 (μmol / g). The ligand immobilization substrate according to 1) or 2) above.
4) The substrate for immobilizing a ligand according to any one of 1) to 3) above, wherein the porous membrane is a non-woven fabric having an average fiber diameter of 0.1 μm to 50 μm.
5) A cell-selective adsorbent comprising at least one affinity ligand having affinity for a specific cell surface immobilized on the ligand-immobilizing substrate according to any one of 1) to 4) above .
6) The cell selective adsorbent according to 5) above, wherein the specific cells are CD4 positive cells.
7) The cell-selective adsorbent according to 5) or 6) above, wherein the affinity ligand is a peptide-type ligand.
8) The cell-selective adsorbent according to 7) above, wherein the peptide-type ligand has a molecular weight of 0.5 to 130 kDa.
9) a step of reacting ammonia and / or a primary amine compound with an epoxy group chemically bonded to at least a surface portion of the porous membrane, and at least a primary amino group and / or a secondary amino group generated by the step A method for producing a substrate for immobilizing a ligand, comprising a step of reacting at least one diglycidyl compound with a porous film on a surface portion.
10) The method for producing a substrate for immobilizing a ligand according to 9) above, wherein the diglycidyl compound is selected from the chemical structure represented by the formula (4).

[Where n in the formula (4) is an integer of 1 to 4. ]
11) The epoxy group chemically bonded to at least the surface portion of the porous film is derived from a polymer obtained by a radiation irradiation graft polymerization method using at least a polymerizable monomer having an epoxy group. The method for producing a substrate for immobilizing a ligand according to 9) or 10) above.
12) A cell selective adsorption column comprising the cell selective adsorbent according to any one of 5) to 8) above.
13) A method for adsorbing target cells in a cell suspension using the cell selective adsorption column described in 12) above.

  In general, when an affinity ligand such as a peptide-type ligand is immobilized on a base material, there is a problem that the affinity inherent in the ligand is not sufficiently expressed. However, when the base material for immobilizing a ligand of the present invention is used, Since the affinity activity of the peptide-type ligand is maintained even after immobilization, the target cells can be effectively selectively adsorbed from a cell suspension such as blood. Moreover, the method for producing a substrate for immobilizing a ligand of the present invention is very simple. Therefore, when the ligand-immobilizing substrate of the present invention is used, a peptide-type ligand excellent in safety and production cost is immobilized, and it has a high selective adsorption property to target cells and is easy to produce. In addition, it is possible to provide a cell selective adsorbent having excellent cost performance.

Hereinafter, the present invention will be described in detail.
Ligand immobilization substrate and cell selective adsorbent material The ligand immobilization substrate of the present invention has at least one chemical structural group represented by the formula (1) chemically bonded to at least the surface portion of the porous membrane. It is characterized by being.

式（１）中のＲ^１は、Ｈ、炭素数１〜５のアルキル基、炭素数１〜５のアルキル基が有する１つ以上の水素原子をＯＨ基で置換した化学構造基、および下記式（２）で示される化学構造基から選ばれる。

R ¹ in formula (1) is H, a chemical structure group in which one or more hydrogen atoms of the alkyl group having 1 to 5 carbon atoms, the alkyl group having 1 to 5 carbon atoms are substituted with an OH group, and the following formula It is selected from chemical structural groups represented by (2).

Ｒ^１がアルキル基の場合、それを構成する炭素数は１〜５個であり、１〜３個が好ましく、１〜２個が特に好ましい。アルキル基としてはメチル基、エチル基、ｎ−プロピル基、イソプロピル基、ｎ−ブチル基、イソブチル基、ｔｅｒｔ−ブチル基、ｎ−アミル基等が挙げられるが、これらには限定されない。炭素数が６個以上になると表面疎水性が高くなるため、細胞選択吸着材として使用する際に細胞の非特異吸着が起こりやすくなり選択性が低下することがあり、またリガンド固定化における立体障害にもなる可能性があるので好ましくない。

When R ¹ is an alkyl group, the number of carbon atoms constituting the alkyl group is 1 to 5, preferably 1 to 3, and particularly preferably 1 to 2. Examples of the alkyl group include, but are not limited to, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, and an n-amyl group. When the number of carbon atoms is 6 or more, the surface hydrophobicity increases, so that non-specific adsorption of cells is likely to occur when used as a cell selective adsorbent, and the selectivity may be lowered, and steric hindrance in ligand immobilization. It is not preferable because there is a possibility of becoming.

  Examples of the chemical structure group obtained by substituting one or more hydrogen atoms of an alkyl group having 1 to 5 carbon atoms with an OH group include, for example, a methylol group or an ethyl group in which one hydrogen of a methyl group is substituted with an OH group. A 2-hydroxyethyl group in which one hydrogen is substituted with an OH group, but is not limited thereto. In this case, the carbon number is 1 to 5, preferably 1 to 3, and particularly preferably 1 to 2. A carbon number of 6 or more is not preferable because it may cause steric hindrance in ligand immobilization.

  N in Formula (1) and Formula (2) is an integer of 1 to 4, but n is preferably 1 to 3, n is more preferably 1 to 2, and n is 1. Is particularly preferred. If n is 5 or more, the surface of the substrate for immobilizing the ligand will have a high surface hydrophilicity, resulting in a structure that suppresses adsorption of proteins and the like, and the epoxy group that is a functional group for immobilizing the ligand is the substrate. Since the probability of existing on the outermost surface of the protein also decreases, it is difficult to sufficiently immobilize the peptide-type ligand.

  The base material for immobilizing a ligand of the present invention is characterized in that at least one chemical structural group represented by the formula (1) is chemically bonded to at least a surface portion of a porous membrane. There is no particular limitation as to how the group is bonded to at least the surface portion of the porous membrane. However, when the chemical structural group represented by the formula (1) is Z, the bond on the surface of the porous film of Z is an acrylic ester or methacrylic ester based film component constituting at least the surface portion of the porous film. A bond as a part of the monomer unit structure represented by the formula (3) contained in the polymer is preferable.

［ここで式（３）中のＲ^２はＨまたはＣＨ_３である］

[Wherein R ² in the formula (3) is H or CH ₃ ]

  Here, the acrylic ester or methacrylic ester polymer may be composed only of the monomer unit structure represented by the formula (3), but other polymerizable monomers (not limited to acrylic ester or methacrylic ester). May be a copolymer containing as a copolymerization component. However, if the total number of monomer units constituting the acrylic acid ester or methacrylic acid ester polymer is M1, and the number of monomer unit structures represented by the formula (3) contained therein is M2, the value of M2 / M1 Is preferably 0.05 to 1, more preferably 0.2 to 1, still more preferably 0.5 to 1, particularly preferably 0.8 to 1, and most preferably 1. When the value of M2 / M1 is less than 0.05, the amount of the epoxy group contained in the ligand-immobilizing base material of the present invention is small, so that the ligand cannot be sufficiently immobilized.

  Here, the other polymerizable monomer is not particularly limited and may be any one. For example, (meth) acrylic acid, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylates, hydroxybutyl (meta ) Acrylates, (meth) acrylic acid, (meth) acrylamide, N-substituted (meth) acrylamide, hydrophilic monomers such as (meth) acrylamides such as N, N-2-substituted (meth) acrylamide, (meth) acrylic acid Typical examples include methyl and vinyl acetate.

  The chemical structural groups of the formulas (1) to (3) should be confirmed by chemical analysis using chemical reactions peculiar to functional groups and comprehensive analysis techniques using several polymer solid surface analysis equipment. Can do. For example, qualitative and quantitative analysis of epoxy groups can be performed using a known sodium thiosulfate test method (see J. Chem. Soc., 1950, 2857). Examples of polymer solid surface analysis equipment include a Fourier transform infrared spectrophotometer (FT-IR), an X-ray photoelectron spectrometer (XPS), an Auger electron spectrometer (AES), and a secondary ion mass spectrometer (SIMS). ), Time-of-flight secondary ion mass spectrometer (TOF-SIMS), solid high-resolution nuclear magnetic resonance analyzer (solid-state NMR), and the like.

  The content of the epoxy group contained in 1 g of the base material for immobilizing a ligand of the present invention is preferably 1 to 500 (μmol / g). Furthermore, it is more preferable that it is 5-400 (micromol / g), and it is especially preferable that it is 10-300 (micromol / g). If the epoxy group content is less than 1 (μmol / g), the ligand may not be immobilized sufficiently, and if it exceeds 500 (μmol / g), excess epoxy group (or more Any other type of immobilization functional group obtained by converting the above becomes a steric hindrance and conversely inhibits the immobilization reaction of ligands, particularly peptide-type ligands.

  The content of the epoxy group contained in 1 g of the ligand-immobilizing base material referred to in the present invention is a value measured according to a known sodium thiosulfate test method (see J. Chem. Soc., 1950, 2857). is there. Specifically, a predetermined amount of the obtained porous membrane is immersed in a sufficient amount of aqueous sodium thiosulfate solution and kept at 80 ° C. for 1 hour, and then a small amount of phenolphthalein is added to react the epoxy group with sodium thiosulfate. This is a method of titrating the amount of OH groups generated in step 1 with an aqueous hydrochloric acid solution, and is a value measured in water to the last.

  Moreover, it is preferable that content of the nitrogen atom which the base material for ligand fixation of this invention has is 10-2000 (micromol / g). Furthermore, it is more preferable that it is 50-1500 (micromol / g), and it is especially preferable that it is 80-1000 (micromol / g). If the nitrogen atom content is less than 10 (μmol / g), the epoxy group content (introduced amount) is inevitably small, and this is not preferable. Even if it exceeds 2000 (μmol / g), the epoxy group content ( This is not preferable because the amount of introduction) tends to be low. The nitrogen atom content of the substrate can be measured with a commercially available pyroluminescence nitrogen analyzer (for example, ANTEK7000 manufactured by ANTEK).

  The porous membrane used in the present invention has a communication hole through which the cell suspension is allowed to pass, and while the cell suspension is passing through the communication hole, the target cell is brought into contact with the affinity ligand present on at least the surface portion of the communication hole. Any structure can be used as long as it is adsorbed. The communication hole is a hole communicating from one membrane surface of the support porous membrane to the opposite membrane surface, and if the liquid can pass through the communication hole, the pore surface of the membrane The shape and the structure inside the film may be anything.

  Examples of the material for forming the porous film include organic polymer compounds such as natural polymers, synthetic polymers, and regenerated polymers, inorganic compounds typified by glass and metal, and organic / inorganic hybrid compounds. Not. Examples of the porous membrane include non-woven fabrics, woven fabrics, knitted fabrics, and meshes manufactured using fibrous materials (solid fibers and hollow fibers) obtained from these materials. In addition, from the state in which an organic polymer material or an inorganic polymer material is melted by heat, in a solution state dissolved by a solvent, or in a state plasticized with a plasticizer, a foaming method, a phase separation method (thermally induced phase separation method or wet method) A sheet-like membrane (flat membrane) or a hollow fiber membrane that can be obtained by a phase separation method), a stretching method, a sintering method, or the like can also be used. Particularly preferred porous membranes used in the present invention include nonwoven fabrics, woven fabrics, knitted fabrics, meshes and the like produced from various fibrous materials from the viewpoint of permeability of cell suspension and cell trapping properties. In particular, a nonwoven fabric is a porous film that is preferably used.

  As a material used for the porous film, an organic polymer material is particularly preferable from the viewpoint of processability. For example, polyalkylene terephthalates, polycarbonates, polyurethanes, poly (meth) acrylates, polyacrylonitrile, polyvinyl alcohol, ethylene / Vinyl alcohol copolymer (Eval), ethylene / vinyl acetate copolymer, polyvinyl acetal, polystyrene, polysulfones, cellulose and cellulose derivatives, polyphenylene ethers, polyethylene, polypropylene, polyvinyl fluoride, polyvinyl chloride, polyfluoride Examples thereof include vinylidene and the like, copolymers of monomers constituting these, and one or more alloys, blends and the like of the above polymers.

In the base material for immobilizing a ligand of the present invention, the structure represented by the above-mentioned formulas (1) to (3) may be distributed almost uniformly from the inside to the surface of the porous membrane, and is unevenly distributed near the surface. It may be a structure. However, even if the structures of the formulas (1) to (3) exist up to the inside of the porous membrane, it is almost irrelevant to the performance of the ligand-immobilizing base material, and conversely, the mechanical strength of the porous membrane is reduced. Therefore, the structures of the formulas (1) to (3) are preferably unevenly distributed near the surface of the porous film. The structure in which the structures of the formulas (1) to (3) are unevenly distributed in the vicinity of the surface of the porous membrane is a porous material manufactured in advance as described in the section of “Manufacturing Method of Ligand Immobilizing Substrate” described later. It can be obtained by a surface chemical reaction method (polymer reaction or graft polymerization reaction) utilizing the surface of a membrane material (nonwoven fabric or the like) or a coating method.
The “surface portion of the porous membrane” referred to in the present invention does not mean, for example, only the front and back sides in the case of a flat membrane, but the surface inside the fine pores (surface of the communicating holes) existing in the flat membrane. Is also included. In particular, when the porous film is a non-woven fabric, the entire surface of the fibers constituting the porous film (excluding the fiber entangled part) is the surface part of the porous film. That is, it refers to the portion of the porous membrane that contacts the target cell suspension.
The cell selective adsorption material of the present invention is obtained by immobilizing at least one kind of affinity ligand having a selective affinity on a specific cell surface on the ligand immobilization substrate of the present invention.

In the present invention, the affinity ligand immobilized on the ligand immobilization substrate is not particularly limited as long as it is a molecule that expresses selective affinity (selective affinity) for a specific cell surface. Examples include the following low molecular compound ligands, organometallic complex ligands coordinated with metal ions, sugar chain ligands, or nucleic acid ligands called RNA aptamers and DNA aptamers. However, as long as excellent cell adsorption ability is expressed, the amino acid sequence that constitutes the variable region of the heavy chain or light chain of the antibody or chimeric antibody having an extremely high affinity for the protein specific to the surface of the target cell Preference is given to the use of ligands of F (ab ′) ₂ , Fab, Fab ′, and other peptides or modified peptides thereof having an amino acid sequence capable of forming a complementarity determining region therein. In particular, when the cell-selective adsorbent of the present invention is used for adsorption removal or recovery of specific cells in blood by the extracorporeal blood circulation method, it is preferable to use a material with low antigenicity in consideration of safety to human body. Since it is preferable that the cost is as low as possible, it is preferable to use a synthetic peptide having a molecular weight smaller than that of an antibody and a modified peptide thereof as a ligand. Further, when such a peptide-type ligand is used, the excellent effect of the ligand-immobilizing base material of the present invention becomes remarkable. Therefore, it can be said that a peptide-type ligand is preferable from this viewpoint.

  Synthetic peptides and modified peptides thereof are artificial molecules created mainly using protein engineering or molecular biology and genetic engineering techniques. Since these are artificial molecules, there is an advantage that a material having excellent thermal stability can be supplied at low cost by mass production. Such molecules are sometimes called artificial antibodies because they bind specifically to the target molecule. Artificial antibodies are usually prepared by randomizing the loop-forming part using a structural molecule similar to the tertiary structure of the antibody V region or incorporating CDR3 of the antibody V gene. For example, Affibody (K. Nord, O. Nord, M. Uhlen, et al., Eur. J. Biochem., 268, 4269 (2001).) In which Protein A is antibodyized, and a luminescent antibody in which GFP is antibodyized. Fluorobody (IS Kim, JH Shim, YT Suh, et al., Biosci. Biotechnol. Biochem., 66, 1148 (2002).), Minibody (fibronectin domain 10 antibodyized) V. Batori, A. Koide, S. Koide, Protein Eng., 15, 1015 (2002).), Pepbody (E. Lunde, V. Lauvrak, IB Rasmussen, a fusion molecule of a peptide mimic molecule and an antibody). et al., Biochem. Soc. Trans., 30, 500 (2002).), Nanobody (A. Muruganandam, J. Tanha, S. Nanang, D. Stanimirobic), a single chain antibody utilizing the structure of a camel antibody. , The FASEB J., 16, 240 (2002).).

  In the case of using a peptide-type ligand, considering safety, the molecular weight is preferably 0.5 to 130 kDa, more preferably 0.5 to 100 kDa, particularly preferably 0.5 to 60 kDa, particularly preferably 0.5 to 40 kDa.

  The target cells that are selectively captured by the cell selective adsorption material of the present invention are not particularly limited, and examples thereof include CD4 positive cells in blood. In this case, a CD4 protein (marker), which is a cell surface marker, is used as a ligand target. And Any cell surface marker that can be used as a target for such selective cell removal can be used, but other examples include lymphocyte surface markers CD4, CD3, CD2, CD1a, CD1b, Each protein such as CD1c, CD2, CD2R, CD5, CD6, CD7, CD8, CD9, CD11a, CD18, CD19, CD20, CD21, CD22, CD23, CD24, CD37, CD40, CD72, CD77, CD79b, CD80, CD81, Other CD13, CD14, CD15, CD16, CD32, CD33, CD34, CD35, CD64, CD65, CDw65, CD66b, CD66e, CD89, CDw90, CD56, CD57, CD94, CD105, CD106, CD46, CD9, CD3 1, CD36, CD41, CD42a, CD42b, CD63, CD11a, CD11b, CD11c, CD1829, CD44, CD48, CD49a, CD49b, CD49c, CD49d, CD49e, CD49f, CD50, CD51, CD54, CD58, CD61, CD62E, CD62L, Examples of the protein include CD62P, CD103, CD26, CD30, CD69, CD70, CD71, CD95, CD25, CD117, CD122, CDw124, CD126, and CD127.

  In the case of the cell selective adsorbent used in blood, the average pore size of the ligand-immobilizing substrate and the cell selective adsorbent of the present invention is 1 μm or more in view of clogging of blood cells and increase in pressure loss. It is preferably 30 μm or less from the viewpoint of cell trapping properties. More preferably, it is 1-20 micrometers, Most preferably, it is 2-10 micrometers. Here, the average pore diameter is a value measured in a PROFIL solution (manufactured by COULTER ELECTRONICS) according to the bubble point method described in ASTM-F316-86.

  The film thickness of the ligand-immobilizing substrate and cell-selective adsorbent of the present invention is preferably 5 mm or less, more preferably because the filtration rate is significantly reduced or the amount of residual liquid after filtration is increased if it is too large. 3 mm or less, most preferably 1 mm or less. On the other hand, if the film thickness is too thin, it leads to film breakage due to strength reduction, etc., and is preferably 1 μm or more, more preferably 5 μm or more, and most preferably 10 μm or more.

When the ligand-immobilizing substrate and the cell-selective adsorbent of the present invention are in a nonwoven fabric shape, the average fiber diameter (average fiber diameter) is preferably 0.1 μm to 50 μm. Furthermore, the average fiber diameter is preferably 0.5 μm to 40 μm, more preferably 1 μm to 30 μm, particularly preferably 1 μm to 20 μm, and most preferably 2 μm to 10 μm. An average fiber diameter of less than 0.1 μm is not preferable because the mechanical strength of the ligand-immobilizing substrate and the cell selective adsorbent decreases. On the other hand, if it exceeds 50 μm, the adsorption surface area when the cell selective adsorbent is used becomes small, and the cell trapping property is lowered, which is not preferable. In addition, the average fiber diameter of the nonwoven fabric referred to in the present invention is dispersed on the imaging screen by taking a photograph of the ligand-immobilizing substrate and the cell-selective adsorbent at a magnification capable of measuring the fiber diameter using a scanning electron microscope. This is a value obtained by measuring 100 or more of the diameters of the fibers being randomly measured and calculating the average value.
The substrate for ligand immobilization and the cell-selective adsorbent of the present invention must have a uniform fiber diameter and pore diameter within the porous membrane (or within the nonwoven fabric) in order to increase the ability to capture cells and prevent clogging. For example, it may have an inclined structure.
Next, a method for producing a ligand-immobilizing substrate and a cell adsorbent according to the present invention will be described.

Method for Producing Ligand Immobilization Base Material The ligand immobilization base material of the present invention comprises a step of reacting ammonia and / or a primary amine compound with an epoxy group chemically bonded to at least a surface portion of a porous membrane, and It can be produced by a production method including a step of reacting at least one diglycidyl compound with a porous film having at least a primary amino group and / or a secondary amino group formed in the step.
Hereinafter, the manufacturing method using a nonwoven fabric as the porous film will be described as an example, but this manufacturing method is not limited to the case where a nonwoven fabric is used.

(Manufacturing process 1)
In the present invention, a process for producing a nonwoven fabric in which an epoxy group is chemically bonded to at least the surface portion of the fiber is necessary. However, the production method is not particularly limited, and any method may be used. .
For example, 1) Non-woven fabric material pre-manufactured by an existing method such as melt blow method, flash spinning method, needle punch method in which short fibers are alternately entangled, and spun bond method for producing non-woven fabric at the same time, A method of manufacturing a nonwoven fabric in which an epoxy group is chemically bonded to at least a surface portion of a fiber by a covalent bond using a chemical reaction on the surface of the fiber. In addition, 2) A method of preparing an appropriate nonwoven fabric by itself using a polymer compound having an epoxy group, 3) A solution prepared by dissolving the polymer compound having an epoxy group in an appropriate solvent, A method of coating the produced nonwoven material, and 4) preparing a polymer solution having a large number of OH groups such as a polymer compound having a reactive functional group, for example, a cellulose derivative, polyvinyl alcohol, ethylene vinyl alcohol copolymer, etc. After coating on a pre-manufactured non-woven material (for example, non-woven fabric having no reactive functional group such as polyethylene, polypropylene, polyester), an epoxy group is introduced by reacting epichlorohydrin or the like with the coating layer. A method is also illustrated.

  The polymer compound having an epoxy group in the methods 2) and 3) is, for example, a polymer having a large number of OH groups such as cellulose derivatives, polyvinyl alcohol, ethylene vinyl alcohol copolymer, and the like in the presence of alkali. Examples include those obtained by reacting hydrin to introduce an epoxy group, and those obtained by copolymerizing a polymerizable monomer having an epoxy group such as glycidyl methacrylate alone or with another monomer.

  Among the above methods, in particular, the method 1) has an epoxy group bonded to the fiber by a covalent bond, so there is a risk of dropping not only the epoxy group but also the functional group bonded from the epoxy group as a starting point after the next manufacturing step. Absent. Therefore, it can be said to be the most preferable production method in the production of the ligand-immobilizing substrate of the present invention.

  When manufacturing a nonwoven fabric in which an epoxy group is chemically bonded to at least a surface portion of a fiber, when using a method of introducing an epoxy group by a surface chemical reaction (covalent bond) to a previously manufactured nonwoven fabric material, the introduction method is It does not specifically limit and various well-known methods can be used. A typical method is an addition reaction of epichlorohydrin in an alkaline solution to a nonwoven fabric made of a polymer material having many OH groups such as cellulose, cellulose derivatives, polyvinyl alcohol, and ethylene vinyl alcohol copolymer. A polymer reaction method, and irradiating non-woven fibers with γ-rays, X-rays, electron beams, ultraviolet rays, etc. to generate radicals on the fiber surface or inside, and having an epoxy group such as glycidyl methacrylate based on this There is a radiation irradiation graft polymerization method in which an epoxy group is introduced by graft polymerization of a reactive monomer. Among these, the radiation-induced graft polymerization method is easy to introduce a sufficient amount of epoxy groups to the nonwoven fabric fiber surface by covalent bonds, and also changes the copolymerization ratio in the copolymerization with different monomers that do not have epoxy groups. Since the amount of epoxy group introduced can be adjusted by controlling the graft ratio, it is particularly preferably used in the method for producing a ligand-immobilizing substrate of the present invention.

  In the method for producing a base material for immobilizing a ligand of the present invention, when an epoxy group is introduced into at least the fiber surface using a coating method, a polymer reaction method, a radiation irradiation graft polymerization method, etc., the raw material nonwoven fabric used is particularly For example, inorganic polymer compounds typified by glass, polyethylene terephthalate, polypropylene, polyethylene, cellulose, cellulose derivatives, polyamide, polyacrylonitrile, polystyrene, polymethyl methacrylate, polyvinylidene fluoride, polyvinyl alcohol, ethylene / vinyl Examples thereof include non-woven fabrics composed of organic polymer compounds typified by alcohol copolymers (eval), ethylene / vinyl acetate copolymers, and organic / inorganic composite polymers composed of both. However, organic polymer materials are preferred because of their formability into nonwoven fabrics and ease of surface chemical modification. Among them, polypropylene, polyethylene, polyvinylidene fluoride, cellulose, polyvinyl alcohol, and ethylene / vinyl alcohol copolymer (Eval) are surface chemical modified. In view of the ease of radiation irradiation, polypropylene, polyethylene, and polyvinylidene fluoride are more preferable for carrying out the radiation-induced graft polymerization method, and the availability of non-woven fabric products and the wide range of grades (average fiber diameter and average pore diameter) are preferred. In consideration, polypropylene and polyethylene are particularly preferable.

  The average fiber diameter (average fiber diameter) of the raw material nonwoven fabric used above is within the range of the average fiber diameter of the ligand-immobilized base material and cell-selective adsorbent of the present invention finally obtained in the range of 0.1 μm to 50 μm. If it becomes, it will not specifically limit. The average pore diameter of the raw material nonwoven fabric is not particularly limited as long as the average pore diameter of the ligand-immobilized base material and the cell selective adsorbent finally obtained is in the range of 1 μm to 30 μm.

  In the method for producing a substrate for immobilizing a ligand of the present invention, when an epoxy group is introduced into at least the surface of a raw nonwoven fabric fiber using a radiation irradiation graft polymerization method, the polymerizable monomer having an epoxy group used for graft polymerization is Although not particularly limited, a monomer capable of radical polymerization is suitable, and glycidyl methacrylate is most suitable from the viewpoint of availability, cost, and ease of handling. In the radiation-induced graft polymerization, a polymerizable monomer having an epoxy group represented by glycidyl methacrylate may be used alone, or if necessary, another type of polymerizable monomer (bonded even if an epoxy group is bonded). And may be copolymerized. However, since it is preferable that the epoxy group is sufficiently introduced into the fiber surface in consideration of the following production process, the charge ratio of glycidyl methacrylate in the charged monomer is preferably 5 to 100 mol% in the graft copolymerization, and 20 -100 mol% is more preferable, 50-100 mol% is further more preferable, 80-100 mol% is especially preferable, and 100 mol% is the most preferable. If the amount is less than 5 mol%, the amount of epoxy groups contained in the base material for immobilizing a ligand of the present invention is small, so that the ligand cannot be sufficiently immobilized.

  Here, the different type of polymerizable monomer is not particularly limited and may be any type. For example, (meth) acrylic acid, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylates, hydroxybutyl (meth) ) Acrylates, (meth) acrylamide, N-1-substituted (meth) acrylamide, hydrophilic monomers such as (meth) acrylamides such as N, N-2 substituted (meth) acrylamide, styrene, (meth) Typical examples include methyl acrylate, acrylonitrile, vinyl acetate and the like.

Moreover, when using the radiation irradiation graft polymerization method, the graft ratio (G) to the raw material nonwoven fabric is preferably 5 to 300%, more preferably 20 to 200%, and particularly preferably 50 to 150%. If the graft ratio is less than 5%, the coating of the fiber surface with epoxy groups will be insufficient, and the amount of functional groups introduced after the next production step 2 and the final ligand immobilization amount are also insufficient. This is not preferable. On the other hand, if the graft ratio exceeds 300%, the physical properties of the nonwoven fabric itself such as the average fiber diameter and the average pore diameter are gradually different from those of the raw material nonwoven fabric, which is not preferable in the design of the adsorbent.
In addition, the graft ratio (G) said here is a value represented by Formula (5).
G (%) = [(weight of nonwoven fabric after grafting−weight of nonwoven fabric before grafting) / (weight of nonwoven fabric before grafting)] × 100 (5)

Irradiation graft polymerization to a nonwoven fabric can be carried out by a conventional method (for example, see Membrane, Vol. 27, No. 4, P196 (2002)). As described above.
Irradiation of the non-woven fabric is performed under oxygen-free conditions, specifically in a nitrogen atmosphere. As radiation, γ rays, X rays, electron beams, and even ultraviolet rays can be used. However, since γ rays have high energy, radical generation efficiency is high, and in order to obtain a high graft rate. Is preferred. An electron beam is preferably used because it has a low energy level but is highly safe and the apparatus is versatile.

  In graft polymerization, a non-woven fabric after radiation irradiation (stored in an oxygen-free atmosphere until graft polymerization is performed) is deoxygenated beforehand by a monomer solution (nitrogen bubbling method or the like) composed of a polymerizable monomer and an appropriate reaction solvent. It is done by immersing in The monomer concentration in the monomer solution is usually in the range of 5 to 20 vol%, but is not limited to this range and is appropriately selected. The solvent is generally preferably one that dissolves the graft polymer chain formed on the surface of the nonwoven fabric by graft polymerization. For example, when glycidyl methacrylate is used as the polymerizable monomer, N-methylpyrrolidone or N, N-dimethyl is used. Formamide and the like are preferably used. Although the graft ratio can be controlled by the polymerization time (that is, the immersion time of the nonwoven fabric in the monomer solution), the reactivity (polymerizability) varies greatly depending on the type of monomer and the raw material nonwoven fabric material, so it is necessary to set appropriately. The reaction temperature is often about 20 to 40 ° C., but is not limited to this range and may be appropriately set. After the polymerization reaction, the excess monomer and the ungrafted homopolymer formed by the chain transfer reaction are sufficiently washed away with an appropriate solvent, and then dried and used in the next production step 2.

  In addition, the mol number of the epoxy group which the nonwoven fabric introduce | transduced at this manufacturing process has can be estimated from the increase in the nonwoven fabric weight before and behind the introduction reaction of an epoxy group. If the increase in weight is small, according to the known sodium thiosulfate test method (see J. Chem. Soc., 1950, 2857.), water is used as a solvent for measurement, and water-soluble as necessary. It can be measured using an organic solvent (such as ethanol or dimethyl sulfoxide) and a mixed solvent thereof.

(Manufacturing process 2)
Next, by reacting ammonia and / or a primary amine compound with the epoxy group chemically bonded to at least the surface portion of the fiber of the nonwoven fabric obtained in the production process 1, primary and / or 2 A primary amino group is generated.
The method of this reaction is not particularly limited, and any method may be used. For example, the method of immersing the nonwoven fabric obtained in production step 1 in a solution in which ammonia or a primary amine compound is dissolved is simple. It is preferably used in the production method of the present invention.
In the case of reacting ammonia, the nonwoven fabric obtained in the production process 1 is immersed in a sufficient amount of a suitable solvent such as water, alcohol (such as methanol or ethanol), dioxane, and then ammonia gas is blown into the solvent. Although a reaction may be carried out, if a commercially available ammonia solution in which ammonia is sufficiently dissolved is used, it is only necessary to immerse the non-woven fabric of production process 1 in it, and it is not necessary to handle dangerous ammonia gas. . Examples of the ammonia solution include an aqueous solution, a methanol solution, an ethanol solution, and a dioxane solution. For example, when an aqueous ammonia solution is used, the concentration of the aqueous ammonia solution is not particularly limited. However, a higher concentration is preferable because the reaction rate is increased, so that the concentration is about 25 to 28 wt%. The reaction may be performed as a mixed solvent in which the above organic solvent is added to an aqueous ammonia solution.

In the case of reacting the primary amine compound, the method of immersing the non-woven fabric obtained in the production step 1 in the primary amine compound itself or in a solution obtained by dissolving it in an appropriate solvent is preferable. The primary amine compound is a compound represented by RNH ₂ , and R affects the surface hydrophilicity / hydrophobicity of the ligand-immobilizing substrate and cell selective adsorbent of the present invention. A thing can be used and is not particularly limited. However, if the hydrophobicity of R becomes too high, the surface hydrophobicity of the final cell selective adsorbent also becomes high, so that nonspecific adsorption of cells tends to occur and the cell selectivity may be lowered. If the molecular weight is too large, it may become a steric hindrance in the addition reaction of the diglycidyl compound in the next production step, and therefore it is not preferred. Therefore, R is preferably selected from a structure in which one or more hydrogen atoms of an alkyl group having 1 to 5 carbon atoms and an alkyl group having 1 to 5 carbon atoms are substituted with an OH group.

When R is an alkyl group, the number of carbon atoms constituting the group is preferably 1 to 5, more preferably 1 to 3, and particularly preferably 1 to 2. Examples of such an alkyl group include, but are not limited to, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, and an n-amyl group. Examples of the structure in which one or more hydrogen atoms of an alkyl group having 1 to 5 carbon atoms are substituted with an OH group include, for example, a methylol group in which one hydrogen of a methyl group is substituted with an OH group, And 2-hydroxyethyl group in which two hydrogen atoms are substituted with OH groups.
Further, hydroxylamine in which R is OH may be reacted as a primary amine compound, but in this case, the same structure as when ammonia is finally reacted is obtained.

  When the primary amine compound is liquid at room temperature, the nonwoven fabric may be immersed in a liquid containing 100% of the primary amine compound, but the primary amine compound is diluted with at least one suitable solvent, The method of immersing the nonwoven fabric in the solution is preferable because there is little waste of the amine compound.

  The solvent for diluting the primary amine compound is not particularly limited as long as it wets the surface of the nonwoven fabric to be immersed to some extent and does not inhibit the reaction between the primary amine compound and the epoxy group. What is necessary is just to select suitably according to the structure of an amine compound. Usable solvents include, for example, alcohols such as methanol, ethanol, propanol and butanol, ketones such as acetone and methyl ethyl ketone, esters such as ethyl acetate, aromatic hydrocarbons such as benzene, toluene and xylene, hexane, Aliphatic hydrocarbons such as cyclohexane, methylcyclohexane and decalin, halogenated hydrocarbons such as chloroform, dichloromethane and dichloroethane, sulfur-containing solvents such as dimethyl sulfoxide, N, N-dimethylformamide, N, N-dimethylacetamide and the like However, alcohols are preferred solvents because they are easy to handle and generally have a high affinity with epoxy groups and amine compounds, and are particularly toxic to the human body. Less Nord practically particularly preferred. If necessary, water may be mixed in advance with these solvents for the purpose of fine adjustment of hydrophilicity / hydrophobicity.

  The amount of the solution containing ammonia and / or the primary amine compound used for immersing the nonwoven fabric having an epoxy group is not a problem as long as the nonwoven fabric to be immersed is sufficiently immersed. During the reaction (dipping), it is preferable to convect (stir) the solution in order to promote a uniform reaction, and ultrasonic irradiation may be performed.

  The amount of ammonia or primary amine compound contained in the solution is preferably 1.5 times mol or more, more preferably 3 times mol or more, more preferably 5 times mol or more of the epoxy group of the nonwoven fabric obtained in the production process 1. Is particularly preferred. If this amount is less than 1.5 times mol of the epoxy group, the reaction with the epoxy group does not proceed sufficiently, or it takes a very long time to achieve a high reaction rate, which is not preferable. In order to obtain a large reaction rate and a high reaction rate between an epoxy group and ammonia and / or a primary amine compound, the amount of ammonia or primary amine compound contained in the solution is preferably as much as possible, but there is no upper limit. In addition, it is useless, and the risk in manufacturing operations (amines are generally irritants) is also increased, so judgment must be made accordingly.

  Although the reaction temperature of the said epoxy group, ammonia, and a primary amine compound is not specifically limited, For example, the temperature range of 20-80 degreeC is suitable. If the reaction temperature is too high, the primary amino group or secondary amino group once generated reacts with a nearby epoxy group, and the aminic proton used for the reaction with the diglycidyl compound in the next production step 3 is very high. This is not preferable because it may be reduced. In order to suppress this reaction, it is preferable that the amount of ammonia or primary amino compound added to the epoxy group is larger.

  In addition, the reaction time (immersion time) of the epoxy group with ammonia and the primary amine compound is not particularly limited. For example, when the reaction is performed by immersing a non-woven fabric having an epoxy group in a 25 wt% aqueous ammonia solution, 1-24 Time is appropriate. After the reaction, excess ammonia and primary amine compound are sufficiently removed by washing with an appropriate solvent, and then dried and used in the next production process.

  The number of moles of nitrogen atoms (N1 (μmol / g)) possessed by 1 g of the obtained nonwoven fabric can be measured with a commercially available pyroluminescence nitrogen analyzer (ANTEK7000 manufactured by ANTEK). Measure the number of moles of nitrogen atoms (N2 (μmol / g)) of 1 g of the nonwoven fabric (created in production process 1) before reacting ammonia and primary amine compound using the apparatus, and insert N2 from N1 By subtracting, the number of moles of nitrogen atoms in the non-woven fabric derived from the primary amino group and / or secondary amino group generated by the reaction with ammonia and / or primary amine compound obtained in this production process is calculated. be able to.

(Manufacturing process 3)
Finally, the ligand-immobilizing base material of the present invention is produced by reacting at least one diglycidyl compound with the non-woven fabric having primary and / or secondary amino groups obtained in the production step 2.
The structure of the diglycidyl compound used in the method for producing a ligand-immobilizing substrate of the present invention is not particularly limited as long as it is a compound having two glycidyl groups in the molecule. However, after the first glycidyl group reacts with the primary and / or secondary amino group of the nonwoven fabric produced in the production process 2, the second glycidyl group remains unreacted, and is described later. Since it is preferably used for ligand immobilization reaction in the production of a cell selective adsorbent, it is preferable that two glycidyl groups exist at positions separated from each other in the molecule, for example, a chemical structure for linking two glycidyl groups. In the case of an aliphatic straight chain, a structure having glycidyl groups at both ends of the straight chain is preferable.

The chemical structure for linking two glycidyl groups is not particularly limited, but an aliphatic linear structure is a preferred structure, and a structure having glycidyl groups at both ends thereof is preferred. The aliphatic straight-chain chemical structure is not particularly limited, but typical structures include an alkylene structure having a repeating structure of —CH ₂ — units and a polyethylene glycol structure having a repeating structure of —CH ₂ CH ₂ O— units. Can be mentioned. In particular, since the polyethylene glycol structure is known as a structure that suppresses nonspecific adsorption of proteins and cells, it is preferable as a chemical structure constituting the diglycidyl compound used in the present invention.

  When the diglycidyl compound has a linear structure having glycidyl groups at both ends, the number of main chain atoms constituting the straight chain connecting two glycidyl groups at both ends is preferably 3 to 50, and more preferably 3 to 30 Preferably, 4 to 13 is preferable, and 4 to 7 is most preferable. Here, the number of main chain atoms constituting a straight chain connecting two glycidyl groups is, for example, when the diglycidyl compound is n = 1 ethylene glycol diglycidyl ether in the following formula (4), the value is 4 is there. If the number of main chain atoms exceeds 50, the epoxy group to be used for ligand immobilization is buried in the aliphatic linear structure and is not effectively used for ligand immobilization.

That is, a preferred structure for the diglycidyl compound used in production process 3 is represented by formula (4). Here, n in the formula (4) is an integer of 1 to 4, preferably n = 1 to 3, more preferably 1 to 2, and particularly preferably 1.

  In the production process 3, the nonwoven fabric obtained in the production process 2 is reacted with at least one diglycidyl compound. The reaction method is not particularly limited as long as the primary amino group and / or secondary amino group on the non-woven fabric can be sufficiently reacted with the epoxy group of the diglycidyl compound, but the non-woven fabric obtained in the production step 2 is at least of the diglycidyl compound. Since the method of immersing in a liquid containing one kind is particularly simple, it is preferably used in the production method of the present invention. In this case, the amount of the diglycidyl compound contained in the liquid to be immersed is derived from the primary and / or secondary amino groups of the nonwoven fabric produced by the reaction with ammonia and / or the primary amine compound in the production process 2. It is preferably 2 mols or more of the amount of nitrogen atoms.

However, since the amino group and the epoxy group of the diglycidyl compound are sufficiently reacted, and one glycidyl group of the diglycidyl compound needs to remain unreacted in order to be used for subsequent ligand immobilization, the liquid in which the nonwoven fabric is immersed The diglycidyl compound contained in is preferably an excess amount with respect to the amount of nitrogen atoms derived from primary and / or secondary amino groups, and is 5 times mol or more of the amount of nitrogen atoms derived from ammonia and / or primary amino groups. Preferably, 10 times mol or more is more preferable, and 30 times mol or more is especially preferable. Further, when the diglycidyl compound is liquid at room temperature, the nonwoven fabric may be immersed in a liquid containing 100% diglycidyl compound.
On the other hand, the method of diluting the diglycidyl compound with one or more suitable solvents and immersing the non-woven fabric in this solution is preferable because there is little waste of the diglycidyl compound and the control of the reaction is easy.

  The solvent for diluting the diglycidyl compound is not particularly limited as long as it wets the surface of the nonwoven fabric to be immersed to some extent and does not inhibit the reaction between the primary and / or secondary amino groups and the epoxy group. And may be appropriately selected according to the structure of the diglycidyl compound. Usable solvents include, for example, alcohols such as methanol, ethanol, propanol and butanol, ketones such as acetone and methyl ethyl ketone, esters such as ethyl acetate, aromatic hydrocarbons such as benzene, toluene and xylene, hexane, Aliphatic hydrocarbons such as cyclohexane, methylcyclohexane and decalin, halogenated hydrocarbons such as chloroform, dichloromethane and dichloroethane, sulfur-containing solvents such as dimethyl sulfoxide, N, N-dimethylformamide, N, N-dimethylacetamide and the like However, alcohols are preferred solvents because they are easy to handle and generally have a high affinity with epoxy groups and amine compounds, and are particularly toxic to the human body. Less Nord practically particularly preferred. If necessary, water may be mixed in advance with these solvents for the purpose of fine adjustment of hydrophilicity / hydrophobicity.

The amount of the liquid containing the diglycidyl compound is not a problem as long as the non-woven fabric to be immersed is sufficiently immersed. During the reaction (dipping), it is preferable to convect (stir) the solution in order to promote a uniform reaction, and ultrasonic irradiation may be performed.
Although the reaction temperature of the said nonwoven fabric and a diglycidyl compound is not specifically limited, For example, the temperature range of 20-80 degreeC is suitable. The reaction time (nonwoven fabric immersion time) is not particularly limited. For example, when the reaction is performed by immersing the nonwoven fabric in a 100% ethylene glycol diglycidyl ether liquid, about 1 to 24 hours is appropriate. After the reaction, the excess diglycidyl compound is sufficiently washed and removed with an appropriate solvent such as alcohol or water and then dried.

Method for producing cell selective adsorbent material The cell selective adsorbent material of the present invention has an affinity for a specific cell surface to the ligand-immobilizing base material of the present invention prepared in the aforementioned production steps 1 to 3. It is produced by immobilizing at least one kind of ligand.
The affinity ligand used in the method for producing a cell selective adsorbent of the present invention and the peptide-type ligand preferably used as the affinity ligand are described in the section “Ligand immobilization substrate and cell selective adsorbent”. .

  The method for immobilizing the ligand is not particularly limited, but the ligand immobilization substrate obtained by the production method of the present invention (the above production methods 1 to 3) is immersed in a solution in which the ligand to be immobilized is dissolved. A method in which a covalent bond is formed by a reaction of a specific functional group (for example, amino group or thiol group) possessed by and an epoxy group of a substrate for immobilizing a ligand is preferable. If the ligand does not have or cannot provide a functional group having high reactivity with an epoxy group such as an amino group or a thiol group, it must be covalently bonded to the substrate using another functional group possessed by the ligand. Therefore, the epoxy group of the ligand-immobilizing base material may be previously converted to another functional group as necessary, and used for ligand immobilization. Examples of functional groups obtained by converting epoxy groups include amino groups, thiol groups, tosyl groups, haloacetamide groups (halo represents halogens such as chloro, bromo, and iodo), and carboxyl groups activated with succinimide. Etc.

  There is no problem as long as the volume of the solution in which the ligand is dissolved is larger than the volume in which the ligand-immobilizing substrate is completely immersed, but if it is too much, there is a concern that the reaction rate may decrease due to the decrease in the ligand concentration or the reaction rate may decrease. In addition, since the ligand is simply wasted, it is not preferable, and a slightly larger volume than the volume in which the ligand-immobilizing substrate is immersed is preferable. There are several cases of ligands such as low molecular weight compound ligands, organometallic complex ligands, protein and peptide ligands, etc., so the reaction solvent (ligand dissolution solvent) is a functional group of the ligand and the epoxy group of the substrate. Any solvent may be used as long as it does not inhibit this reaction or, if necessary, the reaction with a functional group converted from an epoxy group. Further, the reaction temperature (immersion temperature), the reaction time (immersion time) and the like are not particularly limited, and are appropriately set according to the type of functional group that forms a covalent bond and the type of reaction.

When immobilizing a peptide-type ligand that is preferably used in the production method of the present invention, an amino group can be assumed as the functional group of the ligand and reacted with the epoxy group of the substrate. In order to enhance the affinity of the ligand, other functional groups of the ligand (for example, carboxyl group, hydroxyl group, thiol group, etc.) may be used for immobilization of the base material. The epoxy group of the base material for use may be previously converted to another functional group. The reaction solvent (ligand dissolving solvent) is preferably water, and it is particularly preferable to use a phosphate buffer (PBS) having a pH of 7.4. PBS is, for example, 7.6 g of Na ₂ HPO ₄ and 1.8 g of KH ₂ PO ₄ dissolved in 1 L of distilled water.

  The reaction temperature in immobilizing the peptide-type ligand is preferably 10 to 40 ° C. in consideration of avoiding the deactivation of affinity due to heat denaturation while keeping the solubility of the peptide high. The reaction time (immersion time) is preferably 1 to 48 hours. If the reaction time is less than 1 hour, the immobilization reaction may be insufficient, which is not preferable. On the other hand, even if the reaction time is longer than 48 hours, the amount of immobilization does not increase particularly, so it is not particularly necessary.

  When the ligand immobilization is completed under the set reaction conditions, the ligand immobilization substrate is removed from the reaction solution, and an aqueous solution containing a surfactant (for example, 0.2% polyoxyethylene sorbitan monolaurate dissolved in PBS). By washing well with Kanto Chemical's Tween 20 solution), the excess ligand (physically adsorbed to the substrate) (not covalently bonded) is washed away, followed by washing thoroughly with PBS. When the produced cell adsorbent is stored, for example, it can be stored in a refrigerator or in a wet state with PBS, preferably in a refrigerator, but it is preferable to use it early.

Cell selective adsorption column The cell selective adsorption column of the present invention is, for example, one in which a cell selective adsorbent of the present invention is packed in a container having an inlet and an outlet. The cell suspension entered from the column inlet passes through the adsorbent communication hole and comes into direct contact with the ligand immobilized on the porous membrane surface, and then exits from the column outlet. During this time, target cells having affinity for the ligand are selectively adsorbed. The method of passing the cell suspension through the column may be the natural passage of the liquid by its own weight (the method of putting the liquid from the inlet at the high position and letting it out from the outlet at the low position). The method of doing is also preferable. The method of packing the adsorbent into the column is not particularly limited as long as it is arranged so that the cell suspension entered from the column inlet fully contacts the surface of the adsorbent and then exits from the column outlet. A plurality of porous membrane adsorbents cut into squares or circles (for example, square or circular) may be stacked and filled, filled in a roll shape, or filled in a pleat shape. . When a plurality of porous membrane adsorbents are stacked and filled, the same adsorbent may be stacked and filled, and the average pore diameter and average fiber diameter of the adsorbent, the type of ligand, the type of surface functional group, etc. May be stacked and filled as necessary.

  The cell suspension that passes through the cell-selective adsorption column is not particularly limited. For example, a cell suspension obtained from a bioreactor that produces a useful substance for certain cells, blood, lymphocytes, ascites, pleural effusion, bone marrow fluid, etc. Body fluids or liquids containing body fluids. In particular, when the cell suspension is blood, if the cell selective adsorption column of the present invention is incorporated into a circuit that circulates the patient's blood extracorporeally using a driving force such as a pump, a disease treatment method by removing specific cells (especially self It is effective as an immune disease), which is a preferred method of using the cell selective adsorption column of the present invention.

  When the cell selective adsorption column of the present invention is applied to blood extracorporeal circulation therapy, the blood circulation flow rate is preferably 5 to 100 ml / min, although it depends on the volume of the column, the ventilation resistance, and the weight and condition of the patient. 20-80 ml / min is more preferable, and 30-60 ml / min is particularly preferable. If the flow rate is lower than 5 ml / min, it takes a long time for treatment, which is not preferable for the patient. On the other hand, if the flow rate is higher than 100 ml / min, cell selective adsorption is not sufficiently performed, which is not preferable. Similarly, the column volume when applied to extracorporeal blood circulation treatment is preferably 50 to 500 ml, more preferably 100 to 400 ml, and more preferably 150 to 300 ml. If the internal volume of the column is less than 50 ml, the cell adsorption capacity is insufficient, so it is necessary to replace the column with a new one in the middle of treatment, increasing the burden on the patient and increasing the cost of the treated side. Since it connects, it is not preferable. On the other hand, when the volume in the column exceeds 500 ml, the amount of blood taken out from the body always exceeds 500 ml, which is also not preferable because of the physical burden on the patient.

Hereinafter, the present invention will be specifically described based on Examples and Comparative Examples. However, the present invention is not limited by these.
[Example 1]
<1. Production of ligand immobilization substrate>
1-1) Manufacture of non-woven fabric introduced with epoxy group After irradiating polypropylene non-woven fabric (hereinafter abbreviated as PP non-woven fabric, TAPYRUS P080HW-00F, average fiber diameter 3.5 μm) with 100 kGy in a nitrogen atmosphere (The source used is ⁶⁰ Co), methanol of glycidyl methacrylate (hereinafter abbreviated as GMA, manufactured by Wako Pure Chemical Industries, Ltd., reagent grade 1) deoxygenated by nitrogen bubbling method (Wako Pure Chemical Industries, Ltd.) The product was immersed in a special grade reagent) solution (10 vol%). After keeping this solution at 40 ° C. for 25 minutes, the non-woven fabric was taken out and thoroughly washed in dimethylformamide (made by Wako Pure Chemical Industries, Ltd., special grade reagent) (dimethylformamide was changed three times) and further methanol (Wako Pure Chemical Industries, Ltd.). Washing was performed with Yakuhin Co., Ltd. (special grade reagent). By performing air drying for 12 hours and drying under reduced pressure at 40 ° C. for 10 hours, a PP nonwoven fabric (hereinafter abbreviated as PP / PGMA nonwoven fabric) on which GMA was graft-polymerized was obtained. The graft ratio (G) calculated from the weight increase before γ-ray irradiation was 137%. Here, G (%) is a value represented by the following formula (5).
G (%) = [(weight of nonwoven fabric after grafting−weight of nonwoven fabric before grafting) / (weight of nonwoven fabric before grafting)] × 100 (5)
The amount of epoxy group introduced into the PP nonwoven fabric simply calculated from the graft ratio is 4.07 (mmol / g) per 1 g of the nonwoven fabric. However, a predetermined amount of this non-woven fabric is immersed in a sufficient amount of sodium thiosulfate aqueous solution, kept at about 80 ° C. for 1 hour, phenolphthalein is added, and the amount of generated OH groups is titrated with a hydrochloric acid aqueous solution. When the epoxy group content was measured, a value of 65 (μmol / g) was obtained as the number of moles of epoxy group per 1 g of PP / PGMA nonwoven fabric. That is, it is considered that the number of moles of epoxy groups on the nonwoven fabric effectively used in the reaction using water as a solvent is considerably smaller than the value estimated from the calculation.

1-2) Amination of PP / PGMA non- woven fabric 1 g of the PP / PGMA non-woven fabric obtained in 1-1) above is immersed in ethanol (special grade reagent manufactured by Wako Pure Chemical Industries, Ltd.), followed by immersion cleaning with water. Thus, after hydrophilization pretreatment, it was immersed in 30 ml of 25 wt% aqueous ammonia (special grade reagent manufactured by Wako Pure Chemical Industries, Ltd.) (ammonia content was about 440 mmol). After soaking at 25 ° C. for 4 hours, the nonwoven fabric is taken out, washed with distilled water (manufactured by Wako Pure Chemical Industries, Ltd.) until the washing water becomes neutral, dried and aminated PP / PGMA nonwoven fabric. (Hereinafter abbreviated as PP / PGMA (NH3) non-woven fabric).
The nitrogen content of the PP / PGMA (NH3) non-woven fabric and the nitrogen content of the non-woven fabric (PP / PGMA non-woven fabric) before reacting with ammonia were measured with a pyroluminescence nitrogen analyzer (ANTEK 7000, manufactured by ANTEK). From the difference in the values, the nitrogen content introduced by ammonia (which corresponds to almost the same amount as the amino group amount) was 188 (μmol / g) per 1 g of the nonwoven fabric.

1-3) Epoxidation of PP / PGMA (NH3) nonwoven fabric (Manufacture of base material for immobilizing ligand)
1 g of the PP / PGMA (NH3) non-woven fabric obtained in 1-2) above is an ethylene glycol diglycidyl ether (hereinafter abbreviated as EGDE) in which n = 1 in the above-described formula (4), manufactured by Wako Pure Chemical Industries, Ltd. The sample was immersed in 30 ml (0.20 mol) of an electron microscope at 25 ° C., and the whole reaction vessel was gently shaken in that state and kept at 25 ° C. for 22 hours. Thereafter, the nonwoven fabric is taken out, washed 10 times with distilled water, dried under reduced pressure (40 ° C., 12 hours), and a nonwoven fabric in which EGDE is introduced into the PP / PGMA (NH 3) nonwoven fabric (hereinafter PP / PGMA (NH 3) / EGDE). Abbreviated as non-woven fabric).
A predetermined amount of the obtained nonwoven fabric was immersed in a sufficient amount of an aqueous sodium thiosulfate solution and kept at about 80 ° C. for 1 hour. Thereafter, phenolphthalein was added, and the epoxy group content was measured by titrating the amount of generated OH groups with an aqueous hydrochloric acid solution. As a result, the moles of epoxy groups per gram of the obtained nonwoven fabric (ligand immobilization substrate). The number was 136 (μmol / g) (described in Table 1).
Further, the number of moles of nitrogen atoms per 1 g of the obtained nonwoven fabric was measured with a pyroluminescence nitrogen analyzer (ANTEK7000 manufactured by ANTEK), and a value of 175 (μmol / g) was obtained (Table 1). Description).
<2. Manufacture of cell selective adsorbent>
Here, the target cells were CD4 positive cells in human peripheral blood, and a 4H5 anti-human CD4-Fab ′ antibody fragment (hereinafter abbreviated as Fab ′) artificially prepared from a monoclonal antibody was used as a peptide-type ligand.

2-1) A commercially available clone: 4H5 (Medical and Biological Laboratories Co., Ltd.) was used as the mouse anti-human CD4 antibody that was the production source of Fab ′ . This mouse antibody was digested with pepsin, a proteolytic enzyme, for a certain period of time, and cleaved into fragments derived from the F (ab ′) ₂ site and the Fc site. This was purified by gel filtration chromatography to obtain a 4H5 anti-human CD4-F (ab ′) ₂ antibody fragment (hereinafter simply abbreviated as F (ab ′) ₂ ). The number of F (ab ′) ₂ target protein molecule binding sites was bivalent, and the molecular weight was about 100 kDa.
Next, the prepared F (ab ′) ₂ was selectively reduced using 2-mercaptoethanol under mild conditions in the presence of EDTA, and only the disulfide bond at the portion called the hinge site of F (ab ′) ₂ was selectively reduced. did. Next, by reacting an alkylthiol molecule having an SH group at the terminal to block the free SH group, Fab ′ having a monovalent target protein binding site was obtained. The molecular weight of Fab ′ was about 50 kDa.

2-2) Immobilization of Fab ′ on ligand immobilization substrate (production of cell selective adsorbent)
From the PP / PGMA (NH3) / EGDE nonwoven fabric obtained in the above-mentioned “Manufacture of ligand immobilization substrate”, a plurality of circular nonwoven fabrics having a diameter of 7 mm are punched out, and these four sheets are hydrophilized with ethanol in advance. Then, after sufficiently replacing ethanol with a phosphate buffer solution of pH 7.4 (hereinafter abbreviated as PBS), it is completely immersed in 400 μL of Fab ′ solution (concentration is 16 μg / 400 μL) dissolved in PBS (the container is low in protein). Adsorption tube (using M-50081 manufactured by Hitec Co., Ltd.), this state was maintained at 37 ° C. for 48 hours to immobilize Fab ′, and then PBS of 0.2% polyoxyethylene sorbitan monolaurate A cell selective adsorbent targeting CD4 positive cells was obtained by washing thoroughly with a solution (hereinafter, Tween 20 solution (manufactured by Kanto Chemical Co., Inc.)) and PBS.

2-3) Quantification of Fab ′ Immobilization Amount The Fab ′ immobilization amount was determined from the concentration of Fab ′ solution (16 μg / 400 μL) before dipping the PP / PGMA (NH3) / EGDE nonwoven fabric after dipping the nonwoven fabric. As a result of calculating the value obtained by subtracting the concentration of the Fab ′ solution, it was 11 μg per four nonwoven fabrics. The Fab ′ solution concentration before and after immersion in the nonwoven fabric was measured using a BCA protein quantitative reagent (Micro BCA (registered trademark) Protein Assay Reagent Kit 23235 manufactured by PIERCE) and a microplate spectrophotometer (SPECTRA MAX190 manufactured by Molecular Devices, analysis software SOFT). The absorbance was measured by max PRO version 3.0) and quantified.

<3. Evaluation of selective adsorption of CD4 positive cells>
3-1) Cell filtration adsorbent with immobilized blood filtration Fab ′ (four circular nonwoven fabrics with a diameter of 7 mm) was stacked in a 1 ml filter holder (Mobicol polyethylene column, MoBiTec, Germany). . Human fresh whole blood prepared by the method described later was passed through this column at a constant flow rate of 1 ml / min using a syringe pump, and 3 ml of the initial fraction was collected as filtered blood. Fresh human whole blood was dissolved in 1000 ml of distilled water for injection with 100 ml of collected blood in an ACD-A solution (22 g of trisodium citrate dihydrate, 8 g of citric acid monohydrate and 22 g of glucose). And 12.5 ml of a solution filtered through a filter having a pore size of 0.2 μm) was added and mixed.

3-2) Adsorption rate quantification of CD4 and CD8 positive cells In order to evaluate cell selective adsorption, the adsorption rate was measured not only for CD4 positive cells but also for CD8 positive cells.
The leukocyte concentration was measured using an automatic blood cell counter MAX A / L-Retic (BECKMANCOULTER, USA).
About blood before filtration and after filtration, a certain amount of blood was collected, and the abundance ratio of CD4 and CD8 positive cells before and after filtration was analyzed. Various antibodies include Peridin chlorophyll protein-labeled mouse anti-human CD45 (clone 2D1) antibody, and Physicoerythrin-labeled mouse anti-human CD8 (clone SK1) antibody (above, BD Biosciences, USA), mouse anti-Allophycocyanin-labeled human CD3 (clone UCHT1) Antibodies and Fluorescein isothiocyanate mouse anti-human CD4 (clone 13B8.2) antibody (above BECKMANCOULTER, USA) were used. For cell surface analysis, a flow cytometer FACSCalibur and analysis software CELL Quest (above, BD Bioscience, USA) were used. The instrument was adjusted by executing the software FACS Comp (same as above) and then adjusting the compensation with a single-labeled pre-filtration solution. For control of each antibody, isotype control of labeled antibody was used.
The adsorption rate of CD4 and CD8 positive cells was calculated from the results of the leukocyte concentration before and after blood filtration and the abundance ratio of CD4 and CD8 positive cells. As a result, the adsorption rate of CD4 positive cells was 80% and the adsorption rate of CD8 positive cells Was 13%.

[Example 2]
In place of EGDE used in 1-3) of Example 1, a diglycidyl compound of n = 2 in the structure represented by the above-described formula (4) (Nagase ChemteX Corp., Denacol EX-851) was used. A base material for immobilizing a ligand and a cell selective adsorbent were prepared in the same procedure as in Example 1 except that they were used, and the cell selective adsorption rate from human peripheral blood was measured. As a result, the adsorption rate of CD4 positive cells was 45%, and the adsorption rate of CD8 positive cells was 9%. The results obtained, including these values, are listed in Table 1.

Example 3
In place of EGDE used in 1-3) of Example 1, a diglycidyl compound having a structure represented by the above-described formula (4) and having n = 4 (manufactured by Nagase ChemteX Corp., Denacol EX-821) A base material for immobilizing a ligand and a cell selective adsorbent were prepared in the same procedure as in Example 1 except that they were used, and the cell selective adsorption rate from human peripheral blood was measured. As a result, the adsorption rate of CD4 positive cells was 44%, and the adsorption rate of CD8 positive cells was 10%. The results obtained, including these values, are listed in Table 1.

Example 4
Instead of 30 ml of 25 wt% aqueous ammonia used in 1-2 of Example 1, the ethanol solution (30 wt%, monoethanol amine content of monoethanolamine (manufactured by Wako Pure Chemical Industries, Ltd., special grade)) A substrate for ligand immobilization and a cell selective adsorbent were prepared in the same procedure as in Example 1 except that 30 ml of about 130 mmol) was used and PP / PGMA non-woven fabric was immersed in this, and cells from human peripheral blood were prepared. The selective adsorption rate was measured. As a result, the adsorption rate of CD4 positive cells was 74%, and the adsorption rate of CD8 positive cells was 12%. The results obtained, including these values, are listed in Table 1.

Example 5
Instead of 30 ml of 25 wt% aqueous ammonia used in 1-2) of Example 1, 30 ml of ethanol solution of n-propylamine (manufactured by Wako Pure Chemical Industries, Ltd., special grade) (concentration of n-propylamine is 30 wt. %, The content is about 140 mmol), and a substrate for ligand immobilization and a cell-selective adsorbent were prepared in the same manner as in Example 1 except that PP / PGMA nonwoven fabric was immersed in this. The cell selective adsorption rate from blood was measured. As a result, the adsorption rate of CD4 positive cells was 78%, and the adsorption rate of CD8 positive cells was 15%. The results obtained, including these values, are listed in Table 1.

[Comparative Example 1]
PP / PGMA nonwoven fabric prepared in 1-1) instead of PP / PGMA (NH3) / EGDE nonwoven fabric in Example 2-2) (moles of epoxy groups measured in water using sodium thiosulfate method) A cell selective adsorbent was prepared in the same procedure as in Example 1 except that the number was 65 (μmol / g)), and the cell selective adsorption rate from human peripheral blood was measured. As a result, it was found that the adsorption rate of CD4 positive cells was only 32%, the adsorption rate of CD8 positive cells was 11%, and the expression of Fab ′ affinity was insufficient. The results obtained, including these values, are listed in Table 1.

[Comparative Example 2]
Preparation of Fab ′ immobilization beads 2.0 g (value as a suction gel; hereinafter, the weight of the beads means the weight of the suction gel) cellulose beads (manufactured by Chisso Corporation, Cellulofine CPB-06-uc, A particle size of 400 μm and an exclusion limit molecular weight of 2 million) is added to a mixed solution consisting of 40 ml of epichlorohydrin (special grade reagent manufactured by Wako Pure Chemical Industries, Ltd.) and 130 ml of a 0.1 N NaOH aqueous solution, and is shaken at 25 ° C. Shake gently in the tank. After 24 hours, the beads were filtered by suction and washed thoroughly with distilled water until the washing solution became neutral. The epoxy group content per 1 g of the obtained epoxidized beads was 280 (μmol / g) as measured by the sodium thiosulfate aqueous solution method shown in 1-1) of Example 1.
Next, 1.5 g of the obtained epoxidized beads was added to 30 ml of 25 wt% aqueous ammonia (special grade reagent manufactured by Wako Pure Chemical Industries, Ltd.) (ammonia content was about 440 mmol). After gently shaking for 2 hours at 25 ° C., the beads were taken out by suction filtration and washed with distilled water until the washing water became neutral. After drying a part of the aminated beads obtained, the nitrogen content of the beads and the nitrogen content of the epoxidized beads before reacting with ammonia were measured using a pyroluminescence nitrogen analyzer (ANTEK7000 manufactured by ANTEK). From the difference between the measured values, the nitrogen content introduced by ammonia was 370 (μmol / g) per 1 g of beads.
Further, 1.0 g of the obtained aminated beads were immersed in 30 ml (0.20 mol) of EGDE at 25 ° C., and the whole reaction vessel was gently shaken in this state and kept at 25 ° C. for 22 hours. Thereafter, the beads were taken out by suction filtration and washed 10 times with distilled water to obtain beads introduced with EGDE (EGDE-modified beads).
The epoxy group content of the obtained EGDE beads was 268 (μmol / g) per 1 g. The number of moles of nitrogen atoms per gram of beads was 345 (μmol / g) (described in Table 1).

Immobilization of Fab ′ and evaluation of selective adsorption of CD4 positive cells 0.50 g of the above EGDE beads are filled in a 1 mL filter holder (Mobicol polyethylene column, MoBiTec, Germany), and a cap is attached to the liquid outlet. Then, 400 μL of Fab ′ solution dissolved in PBS (concentration: 16 μg / 400 μL) was added and completely immersed, and this state was kept at 37 ° C. for 48 hours. Thereafter, the Tween 20 solution and then PBS were passed through the filter holder and thoroughly washed. The immobilized amount of Fab ′ estimated by the same method as in 2-3) of Example 1 was 9 μg per 0.50 g of beads.
Using the filter holder filled with the EGDE-modified beads obtained by the above operation, the blood filtration operation described in Example 3-1) and the adsorption rate determination operation described in 3-2) were performed. As a result, the adsorption rate of CD4 positive cells was 28%, the adsorption rate of CD8 positive cells was 10%, and the selective adsorption property was insufficient.

The ligand immobilization substrate of the present invention becomes an excellent cell selective adsorbent by immobilizing an affinity ligand having specific affinity on the surface of a specific target cell, and this is filled in a container having an inlet and an outlet. By doing so, it can be used as a cell selective adsorption column from various cell suspensions. In particular, even if a peptide-type ligand is immobilized, the original affinity does not decrease, so that not only cell-selective adsorption but also cost performance is superior, and cell-selective adsorption that is also safe for use in medical applications. It can be used as a column.
Cell suspensions subject to selective cell adsorption include cell suspensions used in bioreactors that produce useful pharmaceutical substances for specific cells, blood, lymph, ascites, pleural effusion, bone marrow, urine, etc. Examples include body fluids and liquids containing these body fluids.
When the cell suspension is blood, if the cell selective adsorption column of the present invention is incorporated in a circuit that circulates the patient's blood extracorporeally using a driving force such as a pump, disease treatment by specific cell removal (for example, CD4 positive cells) ( For example, it is effective for autoimmune diseases such as multiple sclerosis) and useful for the development of an in vitro immunoregulatory treatment system by selective cell adsorption. It can also be used to collect CD34 positive cells from blood (peripheral blood) or bone marrow fluid for the purpose of hematopoietic stem cell transplantation treatment. In addition, it can also be used for therapeutic and diagnostic applications by selective adsorption removal and collection of cancer cells, tumor cells, activated lymphocytes, inflammatory leukocytes, erythroblasts, etc. from body fluids and fluids containing body fluids .

Claims (13)

A base material for immobilizing a ligand, characterized in that at least one chemical structural group represented by the formula (1) containing an epoxy group and a nitrogen atom is chemically bonded to at least a surface portion of the porous membrane.

[Wherein R ¹ in formula (1) is a chemical structural group obtained by substituting one or more hydrogen atoms of H, an alkyl group having 1 to 5 carbon atoms, or an alkyl group having 1 to 5 carbon atoms with an OH group, And selected from chemical structural groups represented by the following formula (2), n in the formulas (1) and (2) is an integer of 1 to 4. ]

When the chemical structural group represented by the formula (1) is Z, the bond of Z on the surface of the porous film is represented by the formula (3) contained in the acrylic acid ester or methacrylic acid ester polymer as the film component. The substrate for immobilizing a ligand according to claim 1, which is a bond as a part of a monomer unit structure.

[Wherein R ² in the formula (3) is H or CH ₃ ]   The content of epoxy groups contained in 1 g of the ligand immobilization substrate is 1 to 500 (μmol / g), and the content of nitrogen atoms is also 10 to 2000 (μmol / g). Item 3. The substrate for immobilizing a ligand according to Item 1 or 2.   The substrate for immobilizing a ligand according to any one of claims 1 to 3, wherein the porous membrane is a nonwoven fabric having an average fiber diameter of 0.1 µm to 50 µm.   A cell selective adsorption material, wherein at least one kind of affinity ligand having affinity for a specific cell surface is immobilized on the ligand immobilization substrate according to claim 1.   The cell-selective adsorbent according to claim 5, wherein the specific cell is a CD4-positive cell.   The cell selective adsorption material according to claim 5 or 6, wherein the affinity ligand is a peptide-type ligand.   The cell-selective adsorbent according to claim 7, wherein the molecular weight of the peptide-type ligand is 0.5 to 130 kDa.   A step of reacting ammonia and / or a primary amine compound with an epoxy group chemically bonded to at least a surface portion of the porous membrane, and at least a primary amino group and / or a secondary amino group generated by the step at least on the surface portion A method for producing a substrate for immobilizing a ligand, comprising the step of reacting at least one diglycidyl compound with the porous membrane of the present invention. The method for producing a substrate for immobilizing a ligand according to claim 9, wherein the diglycidyl compound is selected from chemical structures represented by formula (4).

[Where n in the formula (4) is an integer of 1 to 4. ]   The epoxy group chemically bonded to at least the surface portion of the porous film is derived from a polymer obtained by radiation-induced graft polymerization using at least a polymerizable monomer having an epoxy group. The manufacturing method of the base material for ligand fixation of Claim 9 or 10.   A cell selective adsorption column, which is packed with the cell selective adsorbent according to claim 5.   A method for adsorbing target cells in a cell suspension using the cell selective adsorption column according to claim 12.