EP1231932A1

EP1231932A1 - Implantable substrates for healing connective tissue

Info

Publication number: EP1231932A1
Application number: EP00983161A
Authority: EP
Inventors: Michael Sittinger; Olaf Schultz; Gerd-Rüdiger Burmester
Original assignee: Transtissue Technologies GmbH
Current assignee: Transtissue Technologies GmbH
Priority date: 1999-11-24
Filing date: 2000-11-24
Publication date: 2002-08-21
Also published as: CN1424916A; AU2001601A; DE19957388A1; US6602294B1; US20040028717A1; WO2001037858A1

Abstract

The invention relates to an implantable substrate for healing and protecting connective tissue, preferably cartilage, in the case of arthrosis. The invention also relates to systems and auxiliary means for activating stationary mesenchymal cells for regenerating the tissue. Fine connections are produced between the articular space and the bone marrow space. The articular surface is then covered with multi-layer materials which induce growing-in and maturing of cartilage precursor cells of the bone marrow.

Description

IMP ANTIBLE SUBSTRATES FOR HEALING TISSUE TISSUE

The invention relates to implantable substrates for cartilage healing and protection in osteoarthritis, more precisely an implantable substrate for healing and / or protection of connective tissue, preferably cartilage, comprising at least one structure for cell immigration in vivo and / or for cell matrix formation and / or for the Release of constituents of the agent used and at least one agent for activating local cells for tissue regeneration, a method for its production, a method for healing and / or protection of connective tissue, preferably for cartilage healing and / or protection in arthrosis, using the substrates according to the invention , as well as their use in operative medicine and tissue engineering.

arthrosis

Osteoarthritis is the most common joint disease worldwide, affecting the majority of people over the age of 65. This inevitably results in an enormous clinical, health policy and economic relevance for methods of treating osteoarthritis. In the course of this primarily degenerative age-dependent glaucoma, there is a gradual focal destruction of the joint surface and a reactive, dysregulated regional growth of the adjacent and subchondral bone structures (osteophytes). The result is pain and reduced function and mobility. Systemic factors that influence the development of osteoarthritis are age, gender, weight, osteoporosis, a family history and mechanical overuse. Local factors close the specific Joint shape, misalignments, traumas and specially acting biomechanical factors. Despite the actual degenerative genesis, there are also inflammatory changes in osteoarthrosis such as synovitis (inflammation of the inner skin of the joint) and the production of inflammation-promoting biological messengers (cytokines and growth factors). The ongoing changes represent a dysregulation of tissue homeostasis in the area of load-bearing cartilage and bone structures, a dysbalance between degenerative and reparative processes (WB van den Berg: The role of cytokines and growth factors in cartilage destruction in osteoarthritis, Z Rheumatol. 58 : 136-141, 1999).

The disease is the result of disorders in the area of the entire joint, including the bones, muscles and joint innervation, which ultimately leads to mechanical overuse and biochemically mediated destruction of the affected joints. It is also important that there is no cure for this disease so far: Physiotherapeutic measures and pain-relieving, anti-inflammatory drugs (non-steroidal anti-inflammatory drugs) are often inadequate symptomatic therapies. Conventional orthopedic procedures (debridement, joint shaving, microfracture, drilling) are also insufficiently effective; in the case of pronounced changes, often only the surgical-reconstructive intervention with endoprosthetic joint replacement (JA Buckwalter, HJ Mankin: Articular Cartilage Repair and Transplantation: Arthritis & Rheumatism 41: 1131-1342, 1998).

Cartilage regeneration through tissue engineering with cells and growth factors

Tissue engineering offers promising new technologies by transplanting functionally active autologous cells and, if necessary, shaping biomaterials. With the help of this technology, new cartilage and bone tissue is actively built up or grown. Tissue engineering is usually based on the multiplication of autologous cells, which are then transplanted back into the patient, for example in the form of a solution or as a mature transplant. Unfortunately, the proliferation potential of the cells is limited, and proliferation over many cell passages in vitro significantly reduces the functional quality of the cells.

Another approach in tissue engineering is to assess total tissue regeneration or at least the differentiation of cells previously removed from the patient, e.g. stimulate by adding growth factors. Here, factors of the TGF-ß superfamily are of particular interest because they play a central role in the development of tissues and organs. There are very different principles for tissue engineering to use these factors. For example, genes of the TGF-ß family can be introduced into part of the cells to improve maturation, but also around the tissue e.g. to protect against chronic destruction in a chronically inflamed joint (Evans CH, Robbins PD: Gene therapy for arthritis, Gene therapies: Methods and applications of direct gene transfer, Edited by JA Wolff, Boston, Birkhäuser, 321, (1994); Kalden JR, Geiler T, Herrmann M, Bertling W: Gene therapy for rheumatoid arthritis - an already applicable therapeutic principle? - Z Rheumatol 57: 139-47, (1998); Herndon JH, Robbins PD, Evans CH: Arthritis: is the your in your genes? J Bone Joint Surg Am, 81: 152-7, (1999)).

Another possibility is to use release systems (US Pat. No. 5,910,489), that is to say the temporary release of factors from resorbable microparticles or cell carriers, in order, for example, to stabilize a transplant during the critical phase of healing. Finally, direct tissue regeneration without cells can only be used using growth factors and biomaterials (Kubier, osteoinduction and repair, Oral and Maxillofacial Surgery, 1, 2-25, (1997)). Through the discovery and characterization of ever new factors that can influence the maturation and differentiation of body cells, tools are increasingly available that enable the production of a full-fledged replacement cartilage or bone, starting from only a few autologous cells.

The biggest disadvantage of this technology, however, is the need to first take a tissue sample from the patient and the comparatively complex cultivation of the cells.

Stem cell recruitment, growth factors

Natural tissue healing typically attracts cells from around the defect or injury to fill the lesion. These are mainly progenitor cells, which only develop in the further course through differentiation to the tissue cells with the respective typical properties. In the case of a bone fracture, progenitor cells migrate from the periosteum and from the bone marrow into the defect and form new bones through the detour of a cartilage callus tissue. Natural cartilage regeneration by immigrant progenitor cells practically does not work in humans. However, certain treatment techniques, such as the micro fracture method, aim to open cells from the bone marrow into the joint space.

In the field of cartilage healing, bioactive substances have also been developed which have chemotactic, anti-inflammatory, antiangiogenic, differentiating or antiadhesive properties (US 5,853,746: Methods and compositions for the treatment and repair of defects or lesions in cartilage or bone using functional barrier; US 5,817,773 : Stimulation, production, culturing and transplantation of stem cells by fibroblast growth factors; US 5,910,489: Topical composition containing hyaluronic acid and NSAIDs). The invention has for its object to develop a substrate that can be used in the healing and / or protection of connective tissue, especially cartilage. The object was achieved by providing implantable substrates for healing and / or protection of connective tissue, in particular for cartilage healing and / or protection in the case of arthrosis.

This invention is based in particular on the use or stimulation of pluripotent progenitor cells or mesenchymal stem cells for tissue regeneration, the potential for proliferation and differentiation of which is of particular interest for cartilage or bone healing. In principle, precursors and stem cells can be used in a similar way to adult cells. The differentiation behavior can be influenced by various morphogenic factors, e.g. influence the FGF (fibroblast growth factor) or TGF-β (transforming growth factor beta) superfamily under defined culture conditions (US Pat. No. 5,817,773).

The present invention thus relates to an implantable substrate for healing and / or protection of connective tissue, in particular cartilage, comprising at least one agent for activating local cells for tissue regeneration and at least one structure for cell immigration in vivo and / or for cell matrix formation and / or for the release of components of the agent used.

Furthermore, it relates to a substrate for healing and / or protection of connective tissue, in particular cartilage, comprising at least one agent which contains differentiating factors and chemotactic factors, preferably together with a structure as defined above.

The term “substrate” according to the invention denotes the entirety of the object according to the invention. The substrate according to the invention can, for example, be a can be spreadable or adhesive "cell lock paste" or a kind of "bioactive cartilage plaster". An embodiment of the substrate according to the invention is shown in FIG. 1.

The term “structure for cell immigration in vivo and / or for cell matrix formation and / or for the release of components of the agent used” (structure) encompasses the matrix in which the agent used according to the invention is located.

The term “agent” encompasses all biologically active and inactive constituents which can be used in the context of the present invention and which, as a whole, contribute to the activation of local cells for tissue regeneration.

“Chemotactic factors” are biologically active factors which are suitable, cells, for example cartilage precursor cells from the bone marrow, autologous mesenchymal cells, progenitor cells and stem cells, to the place of treatment or to the place where the substrate according to the invention is located, "To go to".

"Differentiating factors" are biologically active factors which are suitable for inducing cell growth, in particular of the above-mentioned cells and thus tissue build-up.

Surprisingly, it has been possible to provide a substrate with means which can induce and control the migration of tissue precursor cells from the surrounding tissues - in the case of articular cartilage from the bone marrow or synovium. This is done in that the agents contained in the substrate are released during the treatment.

Figure 1 shows a preferred Auslührungsform of the substrate according to the invention, which is constructed schichtfb ^'RMIG. medium

The agents used in the context of the substrate according to the invention are suitable for inducing and controlling the immigration of tissue precursor cells from the surrounding tissues of the sites to be treated. As a rule, the agents are substances which are suitable for mobilizing and / or activating and / or attracting autologous mesenchymal cells, progenitor cells and stem cells. In particular, the agents contain biologically active factors, e.g. chemotactic or chemotactic and differentiating factors. Specifically, the following should be mentioned:

Growth and differentiation factors such as those from the TGF superfamily, FGF family, PDGF, IGF, EGF; cellular adhesion molecules such as Integrins, CD44, selectins, proteoglycans; synthetic peptides, e.g. RGD sequences, e.g. Arginine-glycine-aspartic acid; cytokines; chemotactic factors such as CDMP, CTGF, osteopontin, NO synthesis inhibitor; or extracellular matrix components, e.g. Proteoglycans, fibronectin, collagen.

In addition, depending on the intended use, the agent used according to the invention can comprise the following further components:

Enzymes or their precursors, e.g. Proteases, metalloproteinases, cathepsins;

Inhibitors of enzymes, such as THVIP, antibodies or synthetic blockers of the catalytic center; anti-inflammatory additives such as anti-inflammatory drugs and / or factors. Furthermore, the agent can also contain autologous and non-autologous cells, such as, for example, mesenchymal cells, progenitor cells, stem cells / precursor cells, which in turn can then release corresponding factors.

In a further embodiment, genes or bioactive factors can be transfected into the cells.

The release of two or more components of the agent used according to the invention can take place simultaneously or sequentially and / or from two or more phases / components / layers of the substrate or the structure. Furthermore, the agent used according to the invention and / or the structure used according to the invention can have devices for delayed release of the components.

structures

Furthermore, the substrates according to the invention contain — in one embodiment mandatory and in a further embodiment optionally — suitable structures for cell immigration in vivo and / or for cell matrix formation and / or for the release of constituents of the agent used, in particular the factors contained therein.

The structures according to the invention for cell immigration in vivo and / or for cell matrix formation and / or for the release of constituents of the agent used, in particular the chemotactic and / or differentiating factors, preferably comprise hydrogels;

Sponges (e.g. from collagen);

Wool or wadding-like structures made of polysaccharides (eg cellulose wool, cellulose wadding); natural or synthetic polypeptides (fibrin, polylysine); Braids, fabrics or knitted fabrics made of fibers (eg fibers of resorbable polymers);

Adhesive pastes (e.g. acrylate adhesive), adhesive films (e.g. fibrinogen-coated hyaluronic acid film); ceramic materials or a combination of two or more of these structures.

The structures used according to the invention - and thus also the substrates according to the invention - can have resorbable or non-resorbable properties. Structures with resorbable properties include, for example, hyaluronic acids, preferably those with a molecular weight of 400-600 kD, poly-alpha-hydroxy acids, collagens, alginates, agaroses, fibrins, organic glasses or their combinations. Structures with non-resorbable properties include, for example, ceramic materials or from combinations of ceramic materials with structures that have resorbable properties.

Furthermore, the substrate according to the invention can comprise a structure with several substructures. The substructures which the agents or individual components of these agents used according to the invention can store and release include layers, droplets / spheres or surface coatings. For example, it is possible for a hydrogel comprising an agent according to the invention to be embedded within a lattice structure made of a ceramic material.

The substrate according to the invention can accordingly have a structure in the form of a sponge, in the form of beads, membranes, grids, wadding, bags / pillows, as a liquid, gel or as a multilayer material. In the latter case, the substrate then comprises, for example, a wool-like polymer construct such as polyglycolide, combined with hyaluronic acid and chemotactic growth factors such as osteopontin. In general, the substrates have moldable, brushable or paste-like properties with elastic or plastic mechanical properties and are injectable.

The substrate or the structures therein, if present, can also comprise several phases and / or components and / or layers, which in turn can then release two or more agents.

In a preferred embodiment, mesenchymal stem cells are mixed with hyaluronic acid and injected into the site to be treated.

In a special embodiment, the substrates, e.g. in the form of a multi-layer material to cover the articular surface, a structure that combines on the underside with pins, hollow pins / needles or with anchoring structures, e.g. a Velcro fastener is provided. They can also be designed such that they are e.g. Release cartilage-digesting enzymes - metalloproteinases, hyaluronidase, cathepsins. The pins, hollow needles or anchoring structures are preferably designed to be absorbable.

In a further embodiment, mesenchymal stem cells and / or other connective tissue precursor cells, e.g. Periosteal and perichondrial cells with e.g. Hyaluronic acid injected simultaneously in a double syringe or in succession with separate syringes.

The implantable substrates according to the invention are equipped with the capabilities to mobilize, activate and / or attract autologous mesenchymal cells, progenitor cells and / or stem cells and to proliferate these cells. ration, differentiation and / or maturation. Genes of the bioactive factors mentioned can be transfected into the cells.

Production process The implantable substrate according to the invention for the healing and / or protection of connective tissue, in particular cartilage, is produced by contacting a structure for cell matrix formation and / or cell immigration in vivo and / or for the release of constituents of the agent used and at least one agent for activating local cells for tissue regeneration or by contacting differentiating factors and chemotactic factors, provided that the substrate according to the invention does not comprise a structure in the sense of the invention.

Treatment method The present invention further relates to a method for connective tissue healing and / or protection, in particular in the case of arthrosis, characterized in that the connective tissue is brought into contact with a substrate according to the invention.

The term "connective tissue" in the sense of the present invention encompasses cartilage, bones, tendons and menisci. In a preferred embodiment when using the method according to the invention for cartilage healing and / or protection, connecting channels in the cartilage are brought into contact before the cartilage is brought into contact subchondral space of the cartilage.

In the treatment of, for example, cartilage healing and protection, such substrates can be glued and adapted, for example, over the joint surface with fibrin or acrylate adhesive. The fibrin or acrylate adhesives used are preferably provided with stored chemotactic growth factors (cartilage-derived moφhogenetic protein or connective tissue growth factor). They are stroked over the articular surface and preferably with thrombin to an artificial main superclot solidified. Alternatively, the substrate according to the invention in the form of a double syringe comprises the agent according to the invention, for example differentiating and / or chemotactic factors, in one chamber and thrombin in a second chamber. This variant is used in particular after a microfracture treatment of the site to be treated, it being possible for the biologically active substances (agents) to be introduced into the Superclot.

The inducibility of the agent and / or the release of factors preferably take place from the outside, for example by means of magnetic fields, electrical impulses such as current or voltage, movement or substance injection.

The substrates according to the invention are preferably used after creating channels, for example in the subchondral space, for example through micro-fractures, bores, stitches. The connection channels / bores between the medullary canal and the articular space itself can also be produced by a nail grid, which can be a component of the structure, expediently produced by a Velcro-type anchoring structure with a nail grid underneath.

In a preferred embodiment, this method is characterized in that connecting channels are created between the joint space and the bone marrow space, a sticky cartilage-friendly layer is placed on the arthrotic articular cartilage, cells are attracted from the bone marrow and developed into cartilage tissue in the glued-on layer in a temporary nourishing and promoting environment become. In doing so, substrates are used, the stem structures with channels, which are suitable for establishing connections between the joint space and bone marrow space within previously created multiple fine bores / channels, with which the immigration of tissue precursor cells from the surrounding tissues is induced and structures for cell matrix formation are made possible. The method includes that the substrate comprises structures and / or means with which an articular surface, preferably a multi-layer is covered, and thus induce ingrowth and maturation of cartilage precursor cells from the bone marrow.

The substrate according to the invention has a combination of known (mesenchymal cells, progenitor cells, stem cells / progenitor cells from the bone marrow, bioactive factors) and new elements (connecting channels between the medullary cavity and the articular space; multilayer materials for covering the articular surface that prevent ingrowth and maturation of cartilage precursor cells induce the bone marrow; artificial superclot), which influence one another and result in an advantage (synergistic effect) and the desired success in their new overall effect, which lies in the fact that cells can now be attracted from the bone marrow and can be found in the invention Substrate, e.g. in the multilayer substrates to cover the articular surface to develop cartilaginous tissue. The substrate according to the invention makes it possible to minimize, preferably to replace, the external cultivation and subsequent transplantation of the cultured cells in the patient.

The use of the substrates according to the invention consists in their use in operative medicine and in tissue engineering, in particular in the healing and protection of osteoarthritis and in their use for the proliferation, differentiation and maturation of cells.

The invention will be explained in more detail with the aid of exemplary embodiments.

Examples

example 1

To treat a pronounced arthrotically deformed joint surface, small connections between the bone marrow space and the joint cavity are first made through multiple fine bores (1-2 mm). Subsequently a wool-like polymer construct (polyglycolide) combined with hyaluronic acid and chemotactic growth factors (osteopontin) is glued and adjusted over the joint surface with fibrin or acrylate glue.

Example 2

For the treatment of the articular surface from example 1, after the openings have been made in the medullary canal, fibrin glue with stored chemotactic growth factors (cartilage derived morphogenetic protein or connective tissue growth factor) is brushed over the articular surface and solidified with thrombin (artificial superclot).

List of abbreviations

CD44 - cluster of differentiation

CDMP - cartilage derived moφhogenetic protein CTGF - connective tissue growth factor

EGF - epidermal growth factor

FGF - fibroblast growth factor

IGF - insulin-like growth factor

NO-synthease inhibitors - nitric oxide synthease inhibitors NSAID - non-steroidal-anti-inflammatory drugs

PDGF - platelet derived growth factor (platelet-derived growth factor)

RGD Sequences - Arginine Glycine Aspartic Acid Sequences

PVC - polyvinyl chloride TGF-ß superfamily - transforming growth factor beta superfamily TIMP - tissue inhibitor of metallo proteinases. List of reference symbols applied substance

Connection channels to the bone marrow

Migration of progenitor cells from the bone marrow

Release of bioactive factors in mesenchymal cells, possibly genetically modified

Particles with bioactive factors

covering

Layer with differentiating or tissue-forming factors

Layer with chemotactic factors

Claims

claims

1. Implantable substrate for healing and / or protection of connective tissue, preferably Knoφel, comprising at least one agent for activating local cells for tissue regeneration and at least one structure for cell immigration in vivo and / or for cell matrix formation and / or for the release of components of the used means.

2. Substrate according to claim 1, wherein the at least one agent contains chemotactic factors or differentiating factors and chemotactic factors.

3. Implantable substrate for healing and / or protection of connective tissue, preferably Knoφel, comprising at least one agent that contains differentiating factors and chemotactic factors.

4. Substrate according to one of claims 1 to 3, characterized in that it comprises at least one covering material.

5. Substrate according to one of claims 1 to 4, characterized in that the structures comprise at least one component (a) to (g):

(a) Hydrogels

(b) sponges, collagen sponges

(c) wool / wadding made of polysaccharides, cellulose wool, cellulose wadding (d) natural or synthetic polypeptides, fibrin, polylysine

(e) Braids, knitted fabrics or woven structures made of fibers, preferably fibers comprising resorbable polymers

(f) adhesive pastes, acrylate adhesive, adhesive films, fibrinogen-coated hyaluronic acid film, or (g) ceramic materials.

6. Substrate according to one of claims 1 to 5, characterized in that the at least one agent contains a biologically active factor which is selected from the group consisting of:

Growth and differentiation factors, cellular adhesion molecules, synthetic peptides, cytokines, chemotactic factors and extracellular matrix components.

7. Substrate according to one of claims 1 to 6, characterized in that it further comprises an anchoring structure for anchoring the substrate in or on the site to be treated.

8. A method for producing implantable substrates for healing and / or protection of connective tissue, preferably Knoφel, according to claims 1 to 7, characterized in that a structure for cell matrix formation and at least one means for activating local cells for tissue regeneration are brought into contact with each other or that differentiating factors and chemotactic factors are brought together.

9. A method for connective tissue healing and / or protection, characterized in that the connective tissue is brought into contact with a substrate according to one of claims 1 to 7 or a substrate which can be produced by the method according to claim 8.

10. The method according to Anspmch 9, characterized in that the connective tissue is Knoφel and connecting channels are made in the subchondral space of the Knoφel before bringing the Knoφel into contact with the substrate.

1. Use of a substrate according to one of claims 1 to 7 or a substrate that can be produced according to the method of Anspmch 8 in operative medicine and in tissue engineering.