CRAFTING OF CARTILAGE
A shaped cartilage matrix isolated from a human or animal where the cartilage has been crafted to facilitate disinfection, cleaning, devitalization, recellularization, and/or integration after implantation. Also, a process for repairing a cartilage defect with the cartilage matrix. The matrix is in the form of an osteochondral plug including a cartilage cap ad subchondral bone, wherein one or more gaps, slats, bores, or channels extend through the tidemark at the interface between the cartilage cap and the subchondral bone.
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This application is a continuation of U.S. application Ser. No. 15/661,519, filed Jul. 27, 2017, allowed, which is a continuation of U.S. application Ser. No. 11/826,518, filed Jul. 16, 2007, now U.S. Pat. No. 9,744,043; this application is a continuation-in-part of U.S. application Ser. No. 17/130,832, filed Dec. 22, 2020, which is a continuation of U.S. application Ser. No. 13/537,194, filed Jun. 29, 2012, now U.S. Pat. No. 10,881,515, which is continuation of application Ser. No. 11/826,530, filed Jul. 16, 2007, abandoned; U.S. application Ser. No. 13/537,194 is a continuation-in-part of U.S. application Ser. No. 11/826,522, filed Jul. 16, 2007, abandoned; U.S. application Ser. No. 13/537,194 is a continuation-in-part of U.S. application Ser. No. 11/826,523, filed Jul. 16, 2007, now U.S. Pat. No. 9,125,743; the contents of each of which are incorporated herein by reference.
FIELD OF THE INVENTIONThe invention is directed to producing a shaped cartilage matrix isolated from a human or animal where the cartilage has been crafted to facilitate disinfection, cleaning, devitalization, recellularization, and/or integration after implantation.
BACKGROUND OF THE INVENTIONCartilage is a highly hydrated connective tissue with chondrocytes embedded in a dense extracellular matrix made of, for example, collagen, proteoglycan and water. Although the biochemical composition of cartilage differs according to types, there are mainly three types of cartilage present in a mammal, which include: articular or hyaline cartilage, fibrocartilage, and elastic cartilage. Hyaline cartilage is predominantly found on the articulating surfaces of articulating joints and contains type II collagen and proteoglycans. It is found also in epiphyseal plates, costal cartilage, tracheal cartilage, bronchial cartilage, and nasal cartilage. Fibrocartilage is mainly found in menisci, the annulus fibrosis of the intervertebral disc, tendinous and ligamentous insertions, the symphysis pubis, and insertions of joint capsules. The composition of fibrocartilage is similar to hyaline cartilage except that fibrocartilage contains fibrils of type I collagen that add tensile strength to the cartilage. Elastic cartilage is present in the pinna of the ears, the epiglottis, and the larynx and is similar to hyaline cartilage except that it contains fibers of elastin.
One of the most common cartilage injuries is damage to the fibrocartilage in the knee joint. Meniscal tears are common in young individuals due to sports-related injuries, as well as in older population suffering from degenerative joint diseases. Meniscal allograft transplantation is one of the available treatment options for patients with meniscal tear. Despite some positive results, issues with tissue rejection, disease transmission and a lack of long-term data have limited the use of this approach.
Diseased or traumatized intervertebral disc is another common fibrocartilage injury. The damage on the annulus can cause pain and possible disc herniation that can compress nerves or the spinal cord resulting in arm or leg pain and dysfunction. Recent advances in molecular biology, cell biology and material sciences have opened a new emerging field for cartilage repair.
However, the most common cartilage injury is articular cartilage injury often as a result of sports related trauma. Due to its avascular nature, articular cartilage has very limited capacity for repair. Approximately 500,000 arthroplastic or joint repair procedures are performed each year in the United States. These procedures include approximately 125,000 total hip and 150,000 total knee arthroplastic procedures (Chen, et al., Repair of articular cartilage defects: Part 1, Basic Science of Articular Cartilage Healing, Amer. J. Orthopedics 1999:31-33). Articular cartilage is a complex tissue involving biomechanical function and associated physical stimuli inside the articular cartilage. Articular cartilage is an inhomogeneous material (tissue) and surface loading is converted to mechanical and electrochemical signals by the extracellular matrix through hydraulic and osmotic pressures, fluid and solute/ion flows, matrix deformations and electrical fields (Mow, Van C. and C. C-B. Wang, Some bioengineering considerations for tissue engineering of articular cartilage. Clinical and Orthopedics and Related Research. 1999, Number 367s, 5204-5223).
Unfortunately, chondral defects may not heal, especially when the defect does not penetrate the subchondral bone. A wide variety of surgical procedures are in current use or have been proposed for use to repair chondral defects attempt to prompt the resident cellular population to become more metabolically active thereby promoting new matrix synthesis, however, for the most part, these surgical procedures do little more than provide temporary relief of pain.
SUMMARY OF THE INVENTIONOne aspect of the invention is to produce a devitalized and shaped cartilage graft suitable for recellularizing in vitro, in vivo, or in situ. The devitalized cartilage graft, particularly cartilage graft, may be derived from articular cartilage of human or other animal(s) in some aspects. The subchondral bone, i.e., the cancellous bone portion of the graft, if present, may be cleaned and disinfected to remove bone marrow elements, and the cartilage portion of the graft may be made a cellular. Furthermore, the subchondral bone portion may be crafted into various sizes and shapes and modified to incorporate gaps, a bore, channels, or slots to render cleaning, disinfection, devitalization, and recellularization. The cartilage part of the graft may be treated to improve recellularization by chemical or physical modification. The cartilage may further be recellularized from devitalized cartilage matrix. Moreover, the cartilage graft may be implanted into a recipient and sealed with recipient tissue.
The present invention relates to a cartilage matrix isolated from a human or animal where the cartilage matrix may be crafted, cleaned, and disinfected. A further aspect of the invention relates to a shaped cartilage matrix isolated from a human or animal, wherein the cartilage may be crafted, cleaned, disinfected, and devitalized. An even further aspect of the invention relates to a shaped cartilage matrix isolated from a human or animal, wherein the cartilage may be crafted, cleaned, disinfected, devitalized, and recellularized. A further aspect of the invention relates to the aforementioned shaped cartilage matrix which facilitates the integration after implantation.
The invention further relates to a shaped cartilage matrix isolated from a human or animal where the cartilage has been crafted to facilitate disinfection, cleaning, devitalization, recellularization, and/or integration after implantation. The cartilage matrix may be isolated from whole condyles, whole plateaus, hemicondyles, hemiplateaus, femoral heads, phalanges, talus, tibia, fibula, rib, intervertebral discs, menisci, nose, or an ear. The cartilage matrix may be in the form of whole condyles, whole plateaus, hemicondyles, hemiplateaus, femoral heads, phalanges, talus, tibia, fibula, rib, intervertebral discs, menisci, nose, ear, osteochondral plugs, cartilage discs, cartilage slices, cartilage curls, or cartilage flakes.
A further aspect of the invention relates to a process for repairing a cartilage defect and implantation a cartilage graft into a human or animal by optionally crafting the cartilage matrix into individual grafts, disinfecting and cleaning the cartilage graft, applying a pretreatment solution to the cartilage graft, removing cellular debris using an extracting solution to produce a devitalized cartilage graft, implanting the cartilage graft into the cartilage defect with or without an insertion device, and sealing the implanted cartilage graft with recipient tissue. The devitalized cartilage graft is optionally recellularized in vitro, in vivo, or in situ with viable cells to render the tissue vital before or after the implantation. The devitalized cartilage graft is also optionally stored between the removing cellular debris and the recellularizing steps.
The terms “autologous” (autograft) and “allogenous” (allograft) are used to describe tissues derived from the individual to receive the tissue and tissues derived from an individual other than the individual from the same species to receive the tissue, respectively.
The phrase “cleaning solution” is used to describe a solution to clean allografts, xenografts, and autografts. The phrase cleaning solution is further meant to describe any cleaning solution which may be used to clean and/or disinfect these tissues.
The phrase “decontaminating agent” is used to describe any substance which can be used to decontaminate bone and/or cartilage. Such substances include, but are not limited to, one or more agents which remove or inactivate/destroy any infectious material. Non-exclusive examples of decontaminating agents include antibacterial agents, antiviral agents, and antimycotic agents. Moreover, the phrase decontaminating agents is also meant to include, but is not limited to substances which may clean bone and/or cartilage by inactivating one or more of bacteria, viruses, and/or fungi such as hydrogen peroxide, detergents, and alcohols. Further examples of decontaminating agents include acids such as hydrochloric acid and bases such as hydrogen peroxide.
The term “devitalized” involves the decellularization, or making tissue acellular, such that minimal cellular remnants remain.
The phrase “recellularizable cells” means cells capable of recellularizing a matrix. Examples of such cells include, but are not limited to autologous or allograft chondrocytes isolated from articular cartilage, fibrocartilage, or elastic cartilage; bone marrow aspirate; or stromal cells from bone marrow, synovium, periostieum, perichondrium, muscle, dermis, umbilical cord blood, adipose tissue, or Warton's jelly; or pericytes.
Individual grafts may be crafted out of bone plugs with associated cartilage. Load-bearing osteoimplants may comprise a shaped, compressed composition of bone particles for repairing bone. Moreover, cartilage may be combined with associated cancellous bone in the form of plugs for the repair of cartilage defects. Further, cartilage gel or paste may be inserted in the space between the plug and the wall of the hole created in the cartilage to be repaired. A paste or gel sterile implant material may be made of milled lyophilized allograft cartilage pieces in a bioabsorbable carrier for a cartilage defect. Even further, plugs may be created with a base membrane, a control plug, and a top membrane which overlies the surface of the cartilage covering the cartilage defect and an allograft plug with a cartilage cap which is surface contour matched to the surface of the cartilage defect area to be replaced, respectively.
Demineralized bone matrix (DBM) has substantial osteoconductive activity and may stimulate new bone growth. The intrinsic growth factors in the DBM can recruit recipient progenitor cells and affect the differentiation of the recruited cells into not only osteogenic but also chondrogenic lineage. When DBM was used as a subchondral matrix in a cartilage repair model, subchondral bone growth may be stimulated. In addition, the perichondrium (if used) can be fixed on the DBM to provide cellular source. Because DBM is less deformable and not quickly resorbed, it is believed that it could provide mechanical support to the neocartilage formed on the top, at the beginning of the repair, together with the promotion of bone healing in the bottom of the osteochondral defect. Alternatively, crushed cartilage and cancellous bone from non-load bearing region may be used for cartilage repair.
One aspect of the present invention is directed to the repair of cartilage using cartilage grafts crafted, cleaned, disinfected, devitalized, and optionally recellularized. The devitalized cartilage grafts may be made sterile and preserved using various methodologies. Large devitalized cartilage grafts such as a hemicondyle may be fitted into the surgical site appropriate to the articulation needed to maximize interaction with the opposing cartilage on the bone in apposition to the graft being inserted. Small devitalized osteochondral plugs may be compression fitted into bores drilled into, and covering the cartilage defect such that the cancellous bone part of the graft fits tightly into the bore created using conventional surgical tools and the cartilage part of the graft may be slightly compressed around its perimeter as it is press fitted into the bore. The cartilage part of the graft should be at the same height as the surrounding cartilage of the recipient. The cartilage may be sectioned into slices parallel to the articular surface with various thicknesses. Different sizes and shapes of cartilage can be used to build various contour of the cartilage surface or have cells seeded to regenerate viable cell population in cartilage grafts. The cartilage grafts can also be skived or shaved into curls or flakes with irregular shapes. The cartilage curls and/or cartilage flakes can be mixed with or without a matrix and/or a carrier to become a filler to fill the cartilage defects. In addition, the cartilage curl and/or cartilage flake filler can be applied in combination with a cartilage slice or a cartilage disc or an osteochondral plug to repair a cartilage defect.
The present invention is directed to an cartilage component (part) of a graft which may be made acellular (devitalized) using one or more detergents, enzymes to modify the molecular aspects of the cartilage, and a recombinant endonuclease, for example BENZONASE® (Merk, Inc.). The devitalized graft may be processed to remove residuals of devitalization reagents sufficient to render the graft biocompatible, biohospitable, and recellularizable.
The present invention is also directed to a method and process of clinical use of cartilage components as grafts wherein the surface areas between the recipient and the implanted cartilage graft may be maximized and the interface between the recipient and the implanted cartilage graft may be molecularly cross-linked to control fluid movement when the repaired tissues may be subjected to loading as would occur during normal physiological activities such as, but not restricted to, walking, standing, sitting, running, jogging, or sleeping.
The human femoral condyles, tibial plateaus or femoral heads may be procured from a suitable donor, transported on wet ice to the processing facility, processed as whole or bisected into two hemicondyles or hemiplateaus, or cored out to obtain multiple osteochondral plugs as illustrated in
Many methods can be used to craft osteochondral plugs, the following examples are representative examples and are not meant to be limiting in any respect.
Osteochondral plugs of the present invention may have a length of between about 1 and 20 mm and 8 and 20 mm and may have a diameter at its widest point of between about 8 and 20 mm As illustrated in
Similarly, as illustrated in
The cartilage matrix can also be skived, grated or shaved using a bone fiber shaving device as illustrated in U.S. Patent Application Number 20040059364 to produce cartilage flakes or cartilage curls. This patent application is hereby incorporated by reference in its entirety. The cartilage tissue, such as a femoral condyle, can be fixed on a fixture underneath of a blade mounted in a cutter. The cutter moves horizontally relative to the cartilage tissue during a cutting stroke. The size and thickness of the cartilage flakes or curls can be controlled by adjusting the height of the cutter, the cutting angles, and the distance of each stroke relative to the cartilage tissue. The size of the cartilage flake or curl can be from about 0.001 to about 10 cm3, about 0.001 to about 1 cm3, about 0.01 to about 1 cm3, about 0.1 to about 1 cm3.
The circumferential area of the cartilage portion of an osteochondral plug or a cartilage disc can be further crafted to maximize the circumferential surface and contact areas between the recipient cartilage being repaired and the cartilage graft, as illustrated in
The tapered cylindrical cartilage disc with (38) or without (39) subchondral bone attached can be obtained using a lathe and an angled cutting tool. The diameter of the superficial region of the tapered cylindrical cartilage cap or disc (39) can be larger than the diameter of the deep region that may be connected to the subchondral bone. The straight cylindrical cap (6) or a tapered cylindrical cap (39) can be further crafted to maximize circumferential surface area by embossing with a die that has a straight or non-straight line pattern (40 and 41) or cross-line pattern (42 and 43). The straight cylindrical cap (6) or a tapered cylindrical cap (39) can also be further crafted to maximize the circumferential surface area by spraying or blasting microparticles onto the circumferential surface (44). The microparticles may be selected from a group of but not limited to demineralized bone matrix, freeze dried and fresh ground soft tissue, such as submucosa, fascia, muscle, dermis, cartilage, or amnionic membrane among others. The microparticles can also be microbeads made of biocompatible natural or synthetic polymers, such as collagen, chitosan, alginate, agarose, or hyaluronic acid. The microparticles can also be conjugated with cytokines or bioactive growth supplements. The cytokines may be one or more of, for example, IL-1αR antibody, TNF-α receptor antagonist, cyclooxygenase-2 specific inhibitors, MAP kinase inhibitors, NO synthase inhibitors, NF-κB inhibitors, and inhibitors of MMP. The bioactive growth supplements may be, for example, natural or recombinant FGF-family, TGF-family, IGF-1, PDGF, EGF, VEGF, HGF, PTHrP, Ihh, dexamethasone, insulin, transferrin, selenium, ITS, or ascorbate. The bioactive growth supplements may also be, for example, factors extracted from demineralized bone matrix, basement membrane, or submucosa matrix.
If desired, the circumferential surface and/or superior aspect of the cartilage part of the graft can be microperforated using enzyme linked microparticles as described in U.S. Pat. Nos. 6,432,712 and 6,416,995. These patents are hereby incorporated by reference in their entireties. The size of the microparticles may range from about 20 to about 500 micrometer. Alternatively, the microperforation can be conducted by mechanical or laser drilling on the cartilage such that holes of approximately 20 to 500 micrometer in diameter may be created. The microperforation can be conducted before or after the cleaning, disinfection, devitalization process.
The shaped cartilage grafts can be further cleaned and disinfected. Examples of cleaning solutions and cleaning and disinfection methods are described in U.S. Pat. Nos. 5,556,379, 5,820,581, 5,976,104, 5,977,034, 5,977,432, 5,797,871, and 6,024,735. These patents are hereby incorporated by reference in their entireties.
For the cleaning process, the crafted osteochondral plugs can be placed into a processing chamber (75) shown in
Alternatively, the cleaning process can be conducted by combining optional sonication and vacuum pressure (
After the cleaning and disinfecting process, osteochondral plugs or cartilage discs or slices or flakes or curls can be placed in a processing chamber and devitalized using, for example, one of the following methods: agitating on a shaker or rocker or mixer, or using centrifugal force (
After cartilage grafts are properly placed in the processing chamber or tubes, the cartilage grafts of the osteochondral plugs or discs or slices are optionally modified in a pretreatment solution. The pretreatment solution may be composed of about 0.1 to about 10 U/ml enzymes, such as chondroitinase ABC in a buffer, such as Tris/NaAc among others. The pretreatment step can be conducted, for example, on a shaker or rocker or mixer, or in a processing chamber (75 or 96) under a relative centrifugal force, or under a vacuum pressure less than the ambient pressure, or in a pressure induced flow through system, or under cyclic hydrodynamic pressure. By varying the duration of the pretreatment and the concentration of the chondroitinase ABC in the pretreatment solution, the amount of proteoglycan to be removed can be controlled. Following completion of the pretreatment, the pretreatment solution may be removed from the tubes or the processing chamber (75 or 96) and may be replaced with a rinsing solution. The cartilage grafts can be rinsed in the rinsing solution, such as water, saline, phosphate buffer saline, RPMI media, balanced Hank's solution, Lactated Ringer's solution, DMEM/F12, F12, or DMEM media, among others, in the corresponding processing chamber or tubes. The rinsing solution may be then replaced with an extracting solution (Buffer, sodium dodecylsulfate or N-lauroyl sarcosinate or CHAPS, and BENZONASE® among others) with decontaminating agents to disinfect the tissues and to digest the nucleic acids present in the plugs. The grafts can be incubated in a test tube that fits onto a shaker or rocker or mixer, or in a processing chamber (75 or 96) under a relative centrifugal force, or under vacuum pressure, or in a flow through system, or under cyclic hydrodynamic pressure to induce a fluid flow through the tissue to be devitalized as illustrated in
For devitalization under agitation, osteochondral plugs or cartilage discs or slices or flakes or curls can be placed in one or multiple test tubes that may be fixed on a shaker or rocker or mixer. Cartilage grafts can be incubated with a pretreatment solution on preferably at a temperature from about 4° C. to about 45° C., more preferably from about 15° C. to about 37° C., for a period of time preferably of about 1 to about 24 hours, more preferably of about 1 to about 16 hours, and under agitation preferably of about 10 to about 1000 rpm, more preferably of about 100 to about 500 rpm. Cartilage grafts can be washed with isotonic saline solution preferably at a temperature from about 4° C. to about 42° C., more preferably from about 15° C. to about 37° C., for a period of time preferably of about 10 minutes to about 24 hours, more preferably of about 15 to about 60 minutes, and under agitation preferably of about 10 to about 1000 rpm, more preferably of about 100 to about 500 rpm. After washing with saline two more times, the isotonic saline solution may be replaced by the extracting solution. The test tubes containing cartilage grafts can be incubated preferably at a temperature from about 4° C. to about 45° C., more preferably from about 15° C. to about 37° C., for a period of time preferably of about 1 to about 24 hours, more preferably of about 1 to about 16 hours, and under agitation preferably of about 10 to about 1000 rpm, more preferably of about 100 to about 500 rpm. Following completion of the devitalization process, the tubes may be drained of the extracting solution and replaced with a rinsing solution. The cartilage grafts can be washed in the rinsing solution preferably at a temperature from about 4° C. to about 45° C., more preferably from about 15° C. to about 37° C., for a period of time preferably of about 10 minutes to about 24 hours, more preferably of about 15 to about 60 minutes, and under agitation preferably of about 10 to about 1000 rpm, more preferably of about 100 to about 500 rpm. The washing can be repeated for two more times. The tubes may be then drained of the rinsing solution and replaced with a storage solution. The cartilage grafts can again be incubated on preferably at a temperature from about 4° C. to about 42° C., more preferably from about 15° C. to about 37° C., for a period of time preferably of about 1 to about 24 hours, more preferably of about 1 to about 16 hours, and under agitation preferably of about 10 to about 1000 rpm, more preferably of about 100 to about 500 rpm.
For devitalization under centrifugal force, osteochondral plugs can be fit into the cylindrical step holes in an insert (80 in
For devitalization in a fluid through system (
In detail,
For devitalization under cyclic hydrodynamic pressure (
During devitalization, the pretreatment solution may be transferred into the processing chamber, as well as the rigid tubing and the bottom part of the pressurization chamber (
All the inserts (80, 101, 274, and 118) described above may be designed to be interchangeable among all the processing chambers (75 or 96) in all the devitalization methods. Osteochondral plugs or cartilage discs or slices or flakes or curls from the same donor can be fit into a single processing chamber.
If desired, as described above, after devitalization, the circumferential area of the cartilage graft, such as the cartilage portion of the osteochondral plug, or cartilage discs, or cartilage slices may be further crafted to maximize the surface and contact areas between the boundaries of the recipient cartilage being repaired and the cartilage graft, as illustrated in
The cartilage grafts that have been crafted and devitalized as noted above can be stored in a plasticizer, such as 15-77% glycerol. Suitable storage solutions are well known to those of ordinary skill in the art to which the present invention applies, and such solutions may be readily selected and employed by those of ordinary skill in the art to which the present invention applies without undue experimentation. U.S. Pat. Nos. 6,544,289, 6,293,970, 6,569,200, and 7,063,726 directed toward the use of a water replacing agent for storage of bone and soft tissue. These patents are incorporated by reference in their entireties. After completion of the incubation with storage solution, in one embodiment, the cartilage grafts can be placed in an inner bottle (134) of varying size to accommodate a small (a) or a large graft (b) and completely immersed in the storage solution (
The devitalized cartilage grafts as shown in
The devitalized cartilage graft is intended to be recellularized in situ, in vitro, or in vivo. The devitalized cartilage graft can be removed from the storage container, rinsed, and diluted using an AlloFlow™ chamber among others. Such a chamber is disclosed in U.S. Pat. Nos. 5,879,876 and 6,326,188, which are incorporated by reference in their entireties herein. In one embodiment, the devitalized cartilage graft can be recellularized in situ. The devitalized cartilage graft can be implanted in a cartilage defect in a recipient to render cells from the recipient tissue to migrate into the devitalized cartilage graft, proliferate, differentiate, and secrete endogenous extracellular matrix. In order to facilitate the in situ recellularization, chemical stimuli can be optionally applied. The chemical stimuli can be to coat a devitalized cartilage graft with one or more agent(s) that have bioactive growth supplement or cytokine binding site(s) to increase the affinity of chondrogenic and/or osteoinductive factor adsorption onto the devitalized graft. The chemical stimuli can also be micro-particles that are conjugated with cytokines or bioactive growth supplements and sprayed or blasted onto the cartilage graft before implantation. Alternatively, for in situ recellularization, the devitalized grafts can be recellularized by seeding recellularizable cells, for example, cells isolated from autologous or allogenous soft tissue or bone marrow and/or cultured previously, on to the cartilage graft right before implantation.
If the defect site that needs to be repaired has a curvature, the cartilage graft can be contoured to match the curvature.
In one embodiment, if desired, the cartilage matrix, such as osteochondral plugs, cartilage discs, slices, or flakes or curls can be recellularized in vitro and cultured optionally under chemical and mechanical stimuli for about 1 day to about 40 days to create a viable coherent, contoured, and functional cartilage graft before implantation. The chemical stimuli during the in vitro recellularization and cultivation can be applied by adding one or a cocktail of bioactive growth supplements in the culture media. Alternatively, the chemical stimuli can be applied by coating the devitalized cartilage with one or more agent(s) that has bioactive growth supplement or cytokine binding site(s) through covalent coupling or adsorption to increase the affinity of a bioactive growth supplement or cytokine to the devitalized graft as illustrated previously. Furthermore, chemical stimuli can be applied by sprayed or blasted micro-particles onto the circumferential surface of the devitalized cartilage graft before recellularization. The microparticles may be, but are not limited to, demineralized bone particles; or freeze dried and ground submucosa, fascia, muscle, dermis, or cartilage. The microparticles can also be microbeads made of natural or synthetic materials that are conjugated with cytokines or bioactive growth supplements. The bioactive growth supplements may be one or more of, for example, a natural or recombinant FGF-family, TGF-family, IGF-1, PDGF, EGF, VEGF, HGF, PTHrP, Ihh, dexamethasone, insulin, transferrin, selenium, ITS, or ascorbate. The bioactive growth supplements can also be from extractions of demineralized bone matrix, basement membrane, or submucosa matrix. The cytokines may be, but are not limited to, one or more of, an IL-1.alpha.R antibody, TNF-α receptor antagonist, cyclooxygenase-2 specific inhibitors, MAP kinase inhibitors, NO synthase inhibitors, NF-κB inhibitors, or inhibitors of MMP.
The mechanical stimulus may be applied using a bioreactor. The components of a bioreactor that can provide various modes of mechanical stimuli are illustrated in
The compressed air/gas can be driven by a piston and passes through port (188) through a Luer lock tubing connection (214) to compress the flexible membrane (193). Meanwhile, the compressed air/gas can also pass through port (179) through a Luer lock tubing connection (214) to compress the flexible membrane (172). The piston can be driven by a computer controlled cam and/or stepper motor to move up and down to create a cyclic compression within the bioreactor. The pressure can be monitor using two pressure gauges (110) and regulated by two valves (218). The compressed air/gas may be made of sterile 5% CO2 in air. The bioreactor may be able to fit into an incubator connected to one or two media reservoirs through ports (198, 199, 180, or 179). The cyclic compression can be carried out at pressure preferably of about 0 to about 20 MPa, more preferably of about 0 and about 10 MPa, most preferably of about 0 and about 6 MPa, at a frequency preferably of from about 0.001 to about 5 Hz, more preferably of from about 0.1 to about 3 Hz, and most preferably of from about 0.1 to about 1 Hz, for a period of time preferably of from about 5 minutes to about 16 hours, more preferably of from 5 minutes to about 8 hours, most preferably of from about 5 minutes to about 4 hours every day, and for a total duration preferably of 1 to about 40 days, more preferably of 1 to about 28 days, most preferably of 1 to about 14 days. Alternatively, the cyclic compression can be conducted by inducing compression on the culture media directly to induce pressure on a cartilage graft sandwiched between two porous platens (216 and 217) with or without a confining ring (204) in a bioreactor filled with culture media as illustrated in
Before applying mechanical stimuli, cell seeding on osteochondral plugs can be conducted outside of a bioreactor. Alternatively, cell seeding can be conducted directly in the bioreactor as illustrated in
The cartilage cap and the bone portion of the devitalized osteochondral plug can be recellularized with the same type of cells. Alternatively, the cartilage cap and the bone portion of the devitalized osteochondral plug can be recellularized with different type of cells. Recellularizable cells isolated from autologous or allogenous sources can be seeded on the devitalized cartilage grafts before application of mechanical stimuli. Optionally, a centrifugal force or a positive pressure can be applied to facilitate cell adhesion onto the devitalized cartilage graft. The cartilage cap of the devitalized osteochondral plug can be recellularized with one or more than one type of cells from recellularizable cells. The bone portion of the devitalized osteochondral plug can be recellularized with one or more than one type of cells from recellularizable cells.
As illustrated in
In another embodiment, the bioreactor can be placed horizontally as illustrated in
After cell seeding, the osteochondral plug can be cultured under compression with a loading shaft with or without a spring serially attaching to as illustrated in
If desired, osteochondral plugs seeded with cells can be compressed with cartilage caps opposite each other as illustrated in
Alternatively, a mold that has a desired curvature can be used to replace one of the osteochondral plugs as illustrated in the right panel of
The loading shaft can be driven by a computer controlled cam and/or stepper motor to move up and down to create a cyclic compression within the bioreactor. The compressive stress can be monitored with a load cell (222) and the strain of the loading can be adjusted to obtain the target stress. A flexible bellow (223) can be assembled between the top of the loading shafts (224) and the top chamber assembly (211) to prevent contamination during movements. The bioreactor may be able to fit into an incubator and connected to a media reservoir through ports (198, 199, 180, or 179). Gas exchange can be obtained through port (188), a Luer lock tube connecter (214), and a syringe filter (280). Under compressive stress control, the cyclic compression can be carried out at compressive stress preferably of from about 0 to about 20 MPa, more preferably of from about 0 to about 10 MPa, most preferably of from 0 to about 6 MPa, at a frequency preferably of from about 0.001 to about 5 Hz, more preferably of from about 0.1 to about 3 Hz, and most preferably of from about 0.1 to about 1 Hz, for a period of time preferably of from about 5 minutes to about 16 hours, more preferably of from 5 minutes to about 8 hours, most preferably of from about 5 minutes to about 4 hours every day, and for a total duration preferably of 1 to about 40 days, more preferably of 1 to about 28 days, most preferably of 1 to about 14 days.
In another embodiment of the current invention, cartilage discs or stack of slices can be recellularized and cultured in vitro in a bioreactor as described. Meanwhile, the bone plug that may be cleaned and disinfected without cartilage tissue attached, and/or bony material made from, for example, demineralized bone matrix, hydroxyapatite, ceramics, calcium phosphate, or calcium sulfate in the form of cylinders can be recellularized and cultured separately from the cartilage discs or slices in a bioreactor. After culturing in separation for certain duration, the soft tissue, i.e., the cartilage discs or slices, and the hard tissue, i.e., the bony tissue can be assembled together to be implanted directly or further cultured in a bioreactor to form a composite osteochondral cartilage grafts.
If desired, the devitalized osteochondral plugs, cartilage discs, or cartilage slices can be recellularized in vivo. In one embodiment, the devitalized cartilage grafts can be implanted in a recipient's own soft tissue, for example, under a muscle pouch or a fat pad or other soft tissue containing progenitor or stromal cells for about 7 days to about 3 months. Optionally, before the soft tissue implantation, the devitalized cartilage grafts can be seeded with cells from one or more than one type of cells from recellularizable cells. The devitalized cartilage graft can also be treated with chemical stimuli before or after the in vivo soft tissue implantation. In addition, centrifugal force or positive pressure can be optionally applied to facilitate cell adhesion onto the devitalized cartilage graft. Before implanting into the cartilage defect site in the recipient, the implanted cartilage grafts may be retrieved from the soft tissue, trimmed off the excessive fibrous tissue if present surrounding the recellularized cartilage graft, and rinsed with an isotonic solution, such as isotonic saline. Then the in vivo recellularized graft can be implanted into the target defect site.
Before implantation, a first bore at the cartilage defect site may be created down into the osteochondral bone to remove the damaged cartilage tissue and underlying bone in the recipient. In one aspect, the diameter of the first bore matches the maximum diameter of the bone portion of the osteochondral plug if the osteochondral plug may be chosen to be used as a graft. The length of the first bore can be the same as the osteochondral plug to be implanted. Then, a second shaped bore, such as a star-shaped bore, may be created at the cartilage portion of the first bore. The second shaped bore may be concentric to and on top of the first bore. The second shaped bore can be crafted using a custom designed coring device as illustrated in
After the custom designed coring device cuts through the cartilage tissue and reaches the bone, the adaptor (260) can be removed with the help of a pushing device (67 in
In one embodiment, an osteochondral plug (with or without recellularization in situ, in vitro, or in vivo) can be used to repair the defect site as illustrated in
If a step cylindrical osteochondral plug is used as a graft, the osteochondral plug can fit tightly into the first bore and supported by the wall of the bone portion of the first bore. Alternatively, if the diameter of the bone portion of the step cylindrical osteochondral plug is slightly smaller than the diameter of the first bore in the bone portion of the recipient, a bone filler can be inserted into the bone portion of the first bore that is created at the defect site to fill the gap between the wall of the first bore and the bone portion of the osteochondral plug. The bone filler can also be inserted into the first bore to create a flat surface at the bottom of the first bore so that it can provide support for the osteochondral plug. Meanwhile, the same bone filler can be inserted into the gaps or channels or slots (if present) on the osteochondral plug. In addition, if the cartilage cap of the step cylindrical osteochondral plug fits loosely into the second bore, a cartilage filler can be applied in the gap between the peripheral of the cartilage cap of the osteochondral plug and the second shaped bore. The cartilage filler can also be inserted into gaps or a bore or channels or slots on the cartilage cap from the bottom of the osteochondral plug if such gaps or bore or channels or slots are present. The same or a different photoactive dye used to treat the bores created at the recipient cartilage defect can be used to treat the circumferential area of the cartilage cap of the osteochondral plug. The superficial surface of the osteochondral plug can be at the same height as the surface of the surrounding recipient cartilage surface. If desired the osteochondral plugs can be applied in combination with the cartilage discs or slices or flakes to match the depth and/or contour of the recipient cartilage and to optimize the repair process.
In another embodiment, a cartilage disc (with or without recellularization in situ, in vitro, or in vivo) can be used to repair the defect site as illustrated in
In yet another embodiment, cartilage slices (with or without recellularization in situ, in vitro, or in vivo) can be used to repair the defect site. The cartilage slices can be tailored according to the size, contour, and location of the bore created at the cartilage defect site. A bonding agent, such as a photoactive dye, can be dissolved in an isotonic solution, such as isotonic saline. The shaped second bore on the cartilage tissue along with the first bore at bone portion of the recipient can be filled with the photoactive dye for 5-10 minutes. Then the photoactive dye may be removed and the first bore in the bone portion is optionally rinsed with an isotonic solution, such as isotonic saline. A bone filler can be used to fill up the bone portion of the first bore to provide support for the cartilage slices. The cartilage slices may fit tightly into the shaped second bore. Alternatively, if the cartilage slices fit loosely into the second bore, a cartilage filler can be applied in the gap between the peripheral of the cartilage slices and the second shaped bore. The same or a different photoactive dye used to treat the bores created at the recipient cartilage defect can be used to treat the circumferential area of the cartilage slices. The shaped cartilage slices can be stacked together, optionally a second bonding agent and/or with viable cells seeded between the slices, and inserted into the defect site until at the same height as the surrounding cartilage. The second bonding agent may be the same or different from the bonding agent used to treat the circumferential area of the cartilage slices. If desired the cartilage slices can be applied in combination with the osteochondral plugs, cartilage discs or flakes to match the depth and/or contour of the recipient cartilage and to optimize the repair process.
In another embodiment, cartilage curls or flakes (with or without recellularization in situ, in vitro, or in vivo) can be used to repair the cartilage defect site. The cartilage curls or flakes can also be applied in combination with cartilage slices, discs or osteochondral plugs to repair the cartilage defect site. The cartilage curls or flakes may be applied directly or mixed with a matrix, such as demineralized bone matrix, and/or a carrier, such as hyaluronic acid, isotonic saline, phosphate buffered saline or bone marrow from the implant recipient to form cartilage filler. A bone filler can be used to fill up the bone portion of the first bore to provide support for the cartilage flakes or curls. Then the cartilage curl or flake filler, in a form such as a putty or gel, can be placed into the cartilage defect site directly or injected into the cartilage defect site through a syringe that may be connected to a stent or needle. A stack of cartilage slices or a cartilage disc can be placed on top of the cartilage flake or curl filler with the superficial surface of the stack of the cartilage slice or the cartilage disc being at the same height as the surface of the surrounding recipient cartilage.
The bone filler can be a mixture of a matrix with or without a carrier. The bone filler can be in the format of a sheet, a disc, a tape, a sponge, a cube, a solid or hollow cylinder, particles, gel, or putty. The matrix may be one or more of, for example, autologous crushed bone harvested from the defect site; demineralized bone matrix; cancellous and cortical bone mixture; small intestine submucosa, amniotic membrane, ligament, tendon, skin, muscle tissue, periostieum, or synovial tissue; ceramics; hydroxyapatite; calcium phosphate; calcium sulfate; porous surgical grade titanium or stainless steel; or any combination of the above. The carrier may be one or more of, for example, dihydroxyphenylalanine (DOPA) based adhesive, glucose, concentrated albumin, cyanoacrylate adhesive, gelatin-resorcin-formalin adhesive, chondroitin sulfate aldehyde N-acetylglucosamine (GlcNAc), mussel-based adhesive, poly(amino acid)-based adhesive, cellulose-based adhesive, synthetic acrylate-based adhesives, platelet rich plasma (PRP), monostearoyl glycerol co-Succinate (MGSA), monostearoyl glycerol co-succinate/polyethylene glycol (MGSAPEG) copolymers, or a combination comprising at least one of the foregoing polymers. The carrier can also be one or more of, for example, native or modified collagen, gelatin, agarose, modified hyaluronic acid, fibrin, chitin, biotin, avidin, native or crosslinked chitosan, alginate, demineralized bone matrix, MATRIGEL®, HUMAN EXTRACELLULAR MATRIX®, homogenized connective tissue, proteoglycans, fibronectin, laminin, fibronectin, elastin, heparin, glycerol, or a combination comprising at least one of the foregoing polymers. The carrier may include bioactive growth supplements such as FGF-family, TGF-family, IGF-1, PDGF, EGF, VEGF, HGF, PTHrP, Ihh, dexamethasone, insulin, transferrin, selenium, ITS, or ascorbate. The carrier may also include bioactive growth supplements from the extractions of demineralized bone matrix, basement membrane, or submucosa matrix. The carrier may include cytokines, for example, an ILαR antibody, TNF-α receptor antagonist, cyclooxygenase-2 specific inhibitors, MAP kinase inhibitors, NO synthase inhibitors, NF-κB inhibitors, or inhibitors of MMP. Moreover, the carrier may also include one or more than one type of cells from recellularizable cells. The bone filler may also be a cortical and/or cancellous bone plug.
The cartilage filler may be a mixture of a matrix with or without a carrier. The cartilage filler can be in the format of a sheet, a disc, a tape, a sponge, a cube, a solid or hollow cylinder, particles, gel, or putty. The matrix in the cartilage filler may be one or more of, for example, demineralized bone matrix; small intestine submucosa, amniotic membrane, ligament, tendon, skin, muscle tissue, periostieum, synovial tissue, or devitalized cartilage curls and flakes; or any combination of the above. The carrier in the cartilage filler may be one or more of, for example, dihydroxyphenylalanine (DOPA) based adhesive, glucose, concentrated albumin, cyanoacrylate adhesive, gelatin-resorcin-formalin adhesive, chondroitin sulfate aldehyde N-acetylglucosamine (GlcNAc), mussel-based adhesive, poly(amino acid)-based adhesive, cellulose-based adhesive, synthetic acrylate-based adhesives, platelet rich plasma (PRP), monostearoyl glycerol co-Succinate (MGSA), monostearoyl glycerol co-succinate/polyethylene glycol (MGSAPEG) copolymers, or a combination comprising at least one of the foregoing polymers. The carrier in the cartilage filler may be one or more of, for example, native or modified collagen, gelatin, agarose, modified hyaluronic acid, fibrin, chitin, biotin, avidin, native or crosslinked chitosan, alginate, demineralized bone matrix, MATRIGEL®, HUMAN EXTRACELLULAR MATRIX®, homogenized connective tissue, proteoglycans, fibronectin, laminin, fibronectin, elastin, heparin, glycerol, or a combination comprising at least one of the foregoing polymers. The carrier in the cartilage filler may be one or more of, for example, polymethylmethacrylate, polyurethane, acryloilmorpholine, N,N-dimethyl acrylamide, N-vinyl pyrrolidone and tetrahydrofurfuryl methacrylate, hydroxyapatite, cross-linkage or functionalization of hyaluronan-based collagen and alginate, polyurethane, or polylactic acid. The carrier in the cartilage filler may include one or more of, for example, FGF-family, TGF-family, IGF-1, PDGF, EGF, VEGF, HGF, PTHrP, Ihh, dexamethasone, insulin, transferrin, selenium, ITS, or ascorbate. The carrier in the cartilage filler may include one or more of, for example, bioactive growth supplements extracted from demineralized bone matrix, basement membrane, or submucosa matrix. The carrier in the cartilage filler may include one or more photoactive agents, for example, a xanthene dye, naphthalimide compounds, riboflavin-5-phosphate, N-hydroxypyridine-2-(1H)-thione, N-(20-ethylaminoethyl)-4-amino-1,8-naphthalimide, bis-diazopyruvamide-N,N9-bis(3-diazopyruvoyl)-2,29-(ethylenedioxy)bis-(et-hylamine) (DPD), diazopyruvoyl (DAP), methylene blue, erythrosin, phloxime, thionine, methylene green, rose Bengal, acridine orange, xanthine dye, thioxanthine dyes, ethyl eosin, eosin Y, or a combination comprising at least one of the foregoing photoactive groups. The carrier in the cartilage filler may include one or more antioxidants, for example, sodium nitroprusside, cartilage matrix glycoprotein (CMGP), vitamins C, vitamin E, selenium, N-Acetylcysteine (NAC) estradiol, glutathione, melatonin, resveratrol, flavonoid, carotene, aminoguanidine, or lycopene. The carrier in the cartilage filler may include one or more crosslinking agents, for example, glutaraldehyde; glyceraldehyde; genipin; glucose or ribose; poly(ethylene glycol) diepoxide crosslinker; poly(ethylene glycol) diglycidyl ether; EDC and NHS; transglutaminase; ethylenediamine; lysyl oxidase family; hexamethylene diisocyanate (HMDIC); dimethyl suberimidate (DMS); dimethyl-3-3′-dithiobispropionimidate (DTBP), or acryl azide. The carrier may include cytokines, for example, an IL-1aR antibody, TNF-α receptor antagonist, cyclooxygenase-2 specific inhibitors, MAP kinase inhibitors, NO synthase inhibitors, NF-κB inhibitors, or inhibitors of MMP. The carrier in the cartilage filler may also include one or more than one type of cells from recellularizable cells.
The bonding agent can be one or more of photoactive dye(s) which can be, but are not limited to, xanthene dye, naphthalimide compounds, riboflavin-5-phosphate, N-hydroxypyridine-2-(1H)-thione, N-(2′-ethylaminoethyl)-4-amino-1,8-naphthalimide, bis-diazopyruvamide-N,N9-bis(3-diazopyruvoyl)-2,29-(ethylenedioxy)bis-(et-hylamine) (DPD), diazopyruvoyl (DAP), methylene blue, erythrosin, phloxime, thionine, methylene green, rose Bengal, acridine orange, xanthine dye, thioxanthine dyes, ethyl eosin, eosin Y, and a combination comprising at least one of the foregoing photoactive groups.
The bonding agent may include one or more of, for example, hyaluronidase, chondroitinase, collagenase, trypsin, superoxide dismutase (SOD), or catalase. The bonding agent may include one or more of bioactive growth supplements from the extractions of demineralized bone matrix, basement membrane, or submucosa matrix. The bonding agent may include one or more of bioactive growth supplements such as FGF-family, TGF-family, IGF-1, PDGF, EGF, VEGF, HGF, PTHrP, Ihh, dexamethasone, insulin, transferrin, selenium, ITS, or ascorbate. The bonding agent may include one or more of, for example, dihydroxyphenylalanine (DOPA) based adhesive, glucose, concentrated albumin, cyanoacrylate adhesive, gelatin-resorcin-formalin adhesive, chondroitin sulfate aldehyde N-acetylglucosamine (GlcNAc), mussel-based adhesive, poly(amino acid)-based adhesive, cellulose-based adhesive, synthetic acrylate-based adhesives, platelet rich plasma (PRP), monostearoyl glycerol co-Succinate (MGSA), monostearoyl glycerol co-succinate/polyethylene glycol (MGSAPEG) copolymers, or a combination comprising at least one of the foregoing polymers. The bonding agent may include one or more of, for example, collagen, gelatin, agarose, modified hyaluronic acid, fibrin, chitin, biotin, avidin, native or crosslinked chitosan, alginate, demineralized bone matrix, MATRIGEL®, HUMAN EXTRACELLULAR MATRIX®, homogenized connective tissue, proteoglycans, fibronectin, laminin, fibronectin, elastin, heparin, glycerol, or a combination comprising at least one of the foregoing polymers. The bonding agent may include one or more of, for example, polymethylmethacrylate, polyurethane, acryloilmorpholine, N,N-dimethyl acrylamide, N-vinyl pyrrolidone and tetrahydrofurfuryl methacrylate, hydroxyapatite, cross-linkage or functionalization of hyaluronan-based collagen and alginate, polyurethane, or polylactic acid. The bonding agent may include one or more of, for example, sodium nitroprusside, cartilage matrix glycoprotein (CMGP), vitamins C, vitamin E, selenium, N-Acetylcysteine (NAC) estradiol, glutathione, melatonin, resveratrol, flavonoid, carotene, aminoguanidine, or lycopene. The bonding agent may include one or more of, for example, glutaraldehyde; glyceraldehydes; genipin; glucose or ribose; poly(ethylene glycol) diepoxide crosslinker; poly(ethylene glycol) diglycidyl ether; EDC and NHS; transglutaminase; lysyl oxidase family; hexamethylene diisocyanate (HMDIC); dimethyl suberimidate (DMS); dimethyl-3-3′-dithiobispropionimidate (DTBP); or acryl azide. The bonding agent may also include one or more than one type of cells from recellularizable cells.
The cartilage graft such as osteochondral plugs, cartilage discs, cartilage slices, or cartilage flakes or curls as described above can be cleaned, disinfected, and devitalized; or cleaned, disinfected, devitalized, and recellularized in situ, in vitro, or in vivo.
In one embodiment, in order to easily insert the cartilage graft (such as osteochondral plug, or cartilage disc, or cartilage slices) into the bore created at the recipient cartilage defect site and minimize the compressive force applied on the cartilage graft during insertion, an insertion device (253) can be applied (
A vacuum device (257) or a plunger (258) can be applied to remove the air/gas and/or fluid trapped inside of the bore to allow ambient pressure above the graft to push the cartilage graft into said defect site. The bore created in the recipient tissue at the defect site can be a straight (155) or step cylindrical (255) shape as illustrated in
Alternatively, if a step cylindrical shape osteochondral plug may be used as a graft and fit into a step cylindrical bore (255), the osteochondral plug may be tightly fit into the bore. If gaps, or a bore, or channels, or slots are crafted on the bone portion of the osteochondral plug, the gaps or a bore or channels or slots can be filled with the same bone filler as described above. In all cases, the cartilage cap of an osteochondral plug, or cartilage disc, or cartilage slices can be tightly fit into the bore and supported by the wall of either the bone or cartilage portion of the bore. The superficial surface of the osteochondral plug, cartilage disc, or cartilage slices may be at the same height as the surface of the surrounding recipient cartilage surface. If desired, bone filler can also be injected into the bone portion of the bore in the recipient through the same needle on the insertion device after the cartilage graft has been properly inserted.
After insertion of the cartilage grafts and a time period of about 2 to about 10 minutes, the photoactivated dye, if chosen as one of the bonding agents, can be activated by a laser as illustrated in
Since the delivery system of the laser beams can be small, the procedure described above can be used for both open knee surgery (
Optionally, in addition to sealing the interface between the recipient cartilages being repaired the cartilage graft with photoactivated crosslinking, the bore created on the defect site of the recipient cartilage tissue and the cartilage graft can be coated with additional bonding agents, such as crosslinking agents. Crosslinking agents can be used to facilitate integration of the cartilage graft and the surrounding tissue after implantation and to restore the normal fluid dynamics environment of the cartilage tissue. The crosslinking agents can be chemical or enzymatic and can be, but are not limited to, glutaraldehyde; glyceraldehyde; genipin; glucose or ribose; poly(ethylene glycol) diepoxide crosslinker; poly(ethylene glycol) diglycidyl ether; EDC and NHS, transglutaminase; lysyl oxidase family; hexamethylene diisocyanate (HMDIC); dimethyl suberimidate (DMS); dimethyl-3-3′-dithiobispropionimidate (DTBP), or acryl azide.
EXAMPLES Example 1 Osteochondral Plug, Straight, Step, or Dumbbell ShapeThe distal end of a human femur was procured from a suitable donor, transported on wet ice to the processing facility. A picture was taken and was superimposed on a customer made grid/coordinate system to create a map of the human femoral condyle. The femoral condyle end was “cored” with a coring device or drilled with a hollow cylindrical drill bit to produce multiple cylindrical osteochondral plugs with diameter range from 5-20 mm and the length of the bone portion from 5-20 mm. The coordinate of each individual cylindrical plug was recorded according to the map. The cylindrical plugs were rinsed with isotonic saline. Then one of the cylindrical plugs was inserted into a holder, such as illustrated in
For crafting a dumbbell shape osteochondral plug, 5 mm length of the bone portion right underneath of the cartilage cap of the straight osteochondral plug was cut on a lathe so that the diameter of cut portion was about 70% of the rest part of the osteochondral plug. For crafting a step cylindrical shape osteochondral plug, the entire bone portion of the straight osteochondral plug was cut on a lathe so that the diameter of the bone portion was smaller than that of the cartilage cap of the osteochondral plug. During crafting, isotonic saline was sprayed on the graft through a cooling system installed on the lathe.
Example 2Osteochondral Plug with Gaps, Hollow Cylinder, or Multiple Small Cylindrical Channels
The osteochondral plugs, crafted to be straight, step cylindrical, or dumbbell shape as illustrated in Example 1 can be further crafted to have channels, gaps, or slots, such as osteochondral plugs (8a, 8b, 10, or 14; 22a, 22b, 23, or 25; 30a, 30b, 31, or 33) illustrated in
The length of the bone portion of the osteochondral plug protruding above the top of the holder was adjusted by the custom made bolt (60). Then set screws (57), preferably to be oriented 90 degrees apart, were engaged to further secure the osteochondral plug within the holder (63) and to adjust the centerline of the osteochondral plug to be parallel to the cutting tool centerline or cutting direction. The holder was fit vertically, i.e., with the osteochondral bone portion facing up, into the clamp fixed on the x-y table of the drilling/milling machine so that it could move in a horizontal or cross direction.
An osteochondral plug with gaps as illustrated in 22a in
The osteochondral plug with a hollow cylinder on the bone portion (23) as illustration in
The osteochondral plug with multiple small channels (15) along the whole length of the bone portion up to the cartilage and osteochondral bone interface (25) as illustrated in
Osteochondral Plug with Channels at the Cartilage/Bone Interface
The osteochondral plugs, crafted to be straight, step cylindrical, or dumbbell shape as illustrated in Example 1 can be further crafted to have channels at the cartilage cap and bone portion interface, such as osteochondral plugs (12, 24, or 32) illustrated in
After finishing crafting the first channel, the holder with osteochondral plug inside was rotated 90 degrees to expose the second set of slots (62). Then the second channel was crafted using the same procedure that was used to cut the first channel. During crafting, isotonic saline was sprayed on the graft through a cooling system installed on the milling/drilling machine.
Example 4Osteochondral Plug with Multiple Channels or a Slot at the Cartilage/Bone Interface
The osteochondral plugs, crafted to be straight, step cylindrical, or dumbbell shape as illustrated in Example 1 can be further crafted to have multiple channels or a slot at the cartilage cap and bone portion interface, such as osteochondral plugs (16 or 18; 26 or 27; 34 or 35) illustrated in
Then the rest of the channels were created along the length of the slot. The distance between the centers of the channels was kept at 2.5 mm. For osteochondral plugs with a slot (18, 27, or 35) as illustrated in
The circumferential area of the cartilage portion of an osteochondral plug (as illustrated in example 1-4) or a cartilage disc can be further crafted to maximize the circumferential surface and contact areas between the recipient articular cartilage being repaired and the articular cartilage graft, as illustrated in
The circumferential area of the cartilage portion of an osteochondral plug (as illustrated in Example 1-Example 4) or a cartilage disc can be microperforated to facilitate in situ cell migration from the surrounding tissue to the cartilage graft. The osteochondral plug was fixed in a holder that held the bone portion of the plug inside. The entire cartilage cap protruded outside of the holder. The holder was fixed horizontally, i.e. with centerline of the osteochondral plug being parallel to the horizontal direction, into the clamp fixed on the x-y table of the drilling/milling machine so that it could move horizontal 6r cross direction. A comb of custom made needles, with outer diameter of 350 μm and 1 mm apart, was fixed on the chuck of the drilling/milling machine with a custom made adaptor. The total width of the comb was 9 mm. The punch line was set to be the half of the depth of the cartilage cap and parallel to the cartilage/bone interface. The comb of needles passed through the entire cartilage cap.
Example 7 Cleaning and Disinfecting an Osteochondral Plug Using Centrifugal ForceThe distal end of a human femur was procured from a suitable donor, transported on wet ice to the processing facility. A picture was taken and was superimposed on a customer made grid/coordinate system to create a map of the human femoral condyle. The femoral condyle end was “cored” with a coring device or drilled with a hollow cylindrical drill bit to produce multiple cylindrical osteochondral plugs with diameter range from 5-20 mm and the length of the bone portion from 5-20 mm. The coordinate of each individual cylindrical plug was recorded according to the map. The osteochondral plugs were further crafted into step cylindrical shape and with a slot at the cartilage and bone interface as illustrated in Example 4. The crafted osteochondral plugs with diameters of 14 mm at the cartilage portion and diameter of 10 mm at the bone portion were placed in a processing chamber (75 in
The bone portion of each osteochondral plug was inserted through the center hole of the porous ceramic ring (85) and fit into the bottom portion of the step cylinder hole with the rubber ring (89) on the peripheral surface that created a tight seal. After closing two caps (76 and 79) at the top and bottom of the processing chamber, the chamber was centrifuged at 1000 rcf for 15 minutes at ambient temperature. The bone marrow contained in the cancellous bone part of the osteochondral plug was induced to migrate into the bottom of the processing chamber and discarded. Two hundred and fifty milliliters of AlioWash® solution was transferred into the top portion of the processing chamber. The chamber was centrifuged at 1000 rcf for 1 hour to force the fluid pass through the grafts. Then the solution in both the top and the bottom portion of the chamber was removed and the bottom cap was closed. Two hundred and fifty milliliters of sterile distilled water containing antibiotics were transferred into the top portion of the chamber. The chamber was centrifuged at 1000 rcf for 30 minutes. The solution in both the top and the bottom portion of the chamber was removed and the bottom cap was closed. Two hundred and fifty milliliters of isotonic saline solution was transferred into the top portion of the processing chamber. The chamber was centrifuged at 1000 rcf for 15 minutes. After twice saline wash, the osteochondral plugs were ready for devitalization process.
Example 8 Cleaning and Disinfecting a Hemicondyle Using Vacuum Pressure and SonicationThe distal end of a human femur was procured from a suitable donor, transported on wet ice to the processing facility, and the condyle end was bisected into two hemicondyles. Each hemicondyle was placed in a glass container containing 1 liter of AlioWash® solution and sonicated at 100 Hz for 2 hours. After sonication, the hemicondyle and AlloWash® solution was transferred into a processing chamber similar to the one shown in
Ten cleaned and disinfected step cylindrical osteochondral plugs with channels as illustrated in Example 2, with diameter of 14 mm at the cartilage portion and diameter of 10 mm at the bone portion, were positioned in a processing chamber (75 in
Next, the chamber was drained of saline and 250 mL of 77% (v/v) glycerol was transferred into the top portion of the chamber. The chamber was incubated and centrifuged at 1000 rcf for 2 hours at ambient temperature. The glycerol was drained from the chamber. The devitalized osteochondral plugs were transferred into an inner bag (145 in
Ten fibrocartilage discs isolated from menisci of a cadaver donor, 10 mm in diameter, were positioned into the slots on the stainless steel porous platens on an insert (274) in a processing chamber as illustrated in
Then, five hundred milliliters of pretreatment solution containing 1 unit/mL of chondroitinase ABC in Tris/NaAc buffer in solution reservoir (103) was drawn up from the long spout of the sipper (106), proceeded through the port (105), continued past stopcock (113) and tubing through the roller assembly of the pump (95) through port (98), proceeded through the cartilage graft and insert, then out the bottom of the chamber and through port (78) and continues past stopcocks (114 and 115 and 116), then into the sipper (106) through the short spout and port (107) by using a second pump (117). This cycle continued at 250 mls/minute for 16 hours at 37° C. Then one pump (95) was stopped and another pump (117) was on until the processing chamber was empty. Stopcocks (113, 114, 115, and 116) were turned to redirect the flow to and from the sterile ultra-pure water reservoir (104) and to direct the flow through the resin housing chamber (102). The pumps (95 and 117) were turned on again and the chamber was filled by water exiting sipper (108) out the long spout, into the tubing through stopcock (113), and through the roller pump (95), into the processing chamber (96) through port (98) and proceeds through the cartilage graft and insert, then out the bottom of the chamber and through port (78) and continued past stopcock (114) which directs the flow of water into the resin chamber (102) and out of port (111) and stopcocks (115 and 116) through the tubing and into sipper (109) via the short spout and port (110) and into the water reservoir (104) by using a second pump (117). This cycle continued at 250 mls/minute for 16 hours at ambient temperature. The pressure within the processing chamber was monitored by a pressure gauge (100) that was connected to a port (99). The pretreatment solution reservoir was replaced by an extracting solution reservoir. After removing water from processing chamber, the stopcocks connected to the reservoir containing 500 milliliters of extracting solution was opened and the extracting solution proceeded through the processing chamber at 250 mls/minute for 16 hours at ambient temperature.
The extracting solution consisted of 50 mM Tris-HCl/Tris Base (pH 8.0), 2 mM MgCl2, 0.5% CHAPS, 12 units/mL of endonuclease (Benzonase®, EM Industries, Inc.), and antibiotics sufficient to disinfect the tissue.
Following completion of the devitalization process, the chamber was drained of extracting solution and the stopcock connected to the reservoir containing sterile ultra-pure water was opened. Ultra-pure water proceeded through the processing chamber at 250 mls/minute for 16 hours at ambient temperature. The processing chamber was drained of water and the water reservoir was replaced by a storage solution reservoir. The stopcock connected to the reservoir containing 500 mL of 77% (v/v) glycerol was opened. Glycerol proceeded through the processing chamber at 50 mis/minute for 6 hours at ambient temperature. Then glycerol was drained from the chamber. The devitalized fibrocartilage discs were transferred into an inner bag (145 in
Twenty articular cartilage slices isolated from femoral condyle and cut to be 350-500 micrometer in thickness and 5 to 10 mm in diameter were individually placed in 20 microcentrifuge tubes separately. One milliliter of isotonic saline solution was transferred into each tube. The microcentrifuge tubes were incubated at 37° C. in an orbital shaker for 15 minutes at 1000 rpm. After two more saline washes, one milliliter of extracting solution was transferred into each microcentrifuge tube. The extracting solution consisted of 50 mM Tris-HCl/Tris Base (pH 8.0), 2 mM MgCl2, 16 mM N-lauroyl sarcosinate, 12 units/mL of endonuclease (Benzonase®, EM Industries, Inc.), and antibiotics sufficient to disinfect the tissue. The microcentrifuge tubes containing articular cartilage slices were incubated at 37° C. in an orbital shaker for 16 hours at 1000 rpm.
Following completion of the devitalization process, the tubes were drained of the extracting solution and replaced with 1 mL of isotonic saline. The tubes were incubated at 37° C. in an orbital shaker for 15 minutes at 1000 rpm. The saline wash was repeated two more times. The tubes were drained of extracting solution and replaced with 1 mL of 77% (v/v) glycerol. The tubes were incubated at 37° C. in an orbital shaker for 2 hours at 1000 rpm at ambient temperature.
The devitalized articular cartilage slices were then transferred into an inner bag (145 in 18b(e)) with two ports (147) that sealed with Luer lock caps (148), sealed under vacuum on one edge (146), placed in an outer bag (150) and sealed. Samples from devitalized fibrocartilage discs were used for histology assessment, DNA quantification, or sulfated glycosaminoglycan (GAG) quantification.
Example 12 Devitalizing Osteochondral Plugs and Cartilage Slices Using Cyclic Hydrodynamic PressureFive cleaned and disinfected osteochondral plugs, with diameter of 14 mm at the cartilage portion and diameter of 10 mm at the bone portion, and ten articular cartilage slices, with diameter of 14 mm and thickness of 500 micrometer each, were positioned in a processing chamber (
The osteochondral plugs and cartilage discs were pre-treated with chondroitinase ABC under cycles of hydrodynamic pressure of 0 and 6 MPa for 6 hours at frequency of 1 Hz and at 37° C. The pretreatment solution in the processing chamber was removed. Five hundred milliliters of isotonic saline solution was transferred into the processing chamber. The grafts were then pressurized again under cyclic hydrodynamic pressure for 1 hour. After the saline drained from the processing chamber, five hundred milliliters of extracting solution was transferred into the processing chamber. The extracting solution consisted of 50 mM Tris-HCl/Tris Base (pH 8.0), 2 mM MgCl2, 0.5% CHAPS, 12 units/mL of endonuclease (Benzonase®, EM Industries, Inc.), and antibiotics sufficient to disinfect the tissue. The osteochondral plugs and cartilage slices were processed under cycles of hydrodynamic pressure of 0 and 6 MPa for 16 hours at ambient temperature.
Following completion of the devitalization process, the processing chamber was drained of extracting solution and replaced with 500 mL of isotonic saline. The grafts were pressurized again under cyclic hydrodynamic pressure for 1 hour. The saline wash was repeated two more times. The chamber was drained of saline and 500 mL of 77% (v/v) glycerol was transferred into the processing chamber. The grafts were pressurized again under cyclic hydrodynamic pressure for 2 hours at ambient temperature. Then, the glycerol was drained from the chamber.
The devitalized osteochondral plugs or the stack of cartilage slices along with the contoured porous platen were transferred into an inner sealed box (141) and the inner box was placed in an outer box (143) and sealed (c in
Devitalization of Articular Cartilage Using Chondroitinase ABC and/or CHAPS Made of Benzonase on a Shaker
Frozen human articular cartilage obtained from cadaver with donor consent was used for the experiments. The 5-7 mm diameter cartilage discs without subchondral bone were pretreated with a pretreatment solution composed of 1 unit/mL of chondriotinaseABC in 50 mM Tris/60 mM NaAc buffer supplemented with protease inhibitors and bovine serum albumin at 37° C. and 1,000 rpm on a shaker for 24 hours. The cartilage discs were washed with isotonic saline for 15 minutes at 37° C. for a total of three times. Two samples were stored at 4° C. as chondroitinase controls.
The rest of samples were devitalized in an extracting solution, composed of 0.5% CHAPS, 11.5 units/mL Benzonase, 50 mM Tris, and 2 mM MgCl2, at 37° C. and 1000 rpm in a shaker for 24 hours. The cartilage samples were washed twice with isotonic saline for 1 hour at 37° C.
The resulting cartilage was used for DNA, GAG quantification, Haematoxylin & Eosin and Safranin 0 staining. A Quant-it PicoGreen dsDNA kit was used to quantify the residual DNA in the cartilage. The GAG content was quantified by dimethylmethylene blue (DMMB) assay.
The groups treated with chondroitinase or CHAPS/Benzonase showed significantly lower residual dsDNA compared to cryopreserved control. The combination of chondroitinase ABC and CHAPS/Benzonase gave the most DNA reduction (>98%).
The histology sections, stained with Haematoxylin & Eosin and Safranin 0, showed that significant reduction of nucleus staining was found in cartilage groups treated with chondroitinase ABC and CHAPS/Benzonase. Inter-territorial matrix removal was found in cartilage treated with chondroitinase ABC and CHAPS/Benzonase, while territorial matrix reduction was found at the surfaces that were exposed to the pretreatment or extracting solution directly (
Microperforation of the Cartilage Cap with Agarose Bead Immobilized TPCK Trypsin after Devitalization
After devitalization, the cartilage portion of an osteochondral plug (as illustrated in Example 1-Example 4) or a cartilage disc can be microperforated to facilitate recellularization in vitro, vivo, and in situ. Five cylindrical osteochondral plugs, 7 mm in diameter and 10 mm in length, were placed in a sterile glass beaker. Five milliliters of agarose beads immobilized with TPCK trypsin (Pierce, Rockford, Ill.) were washed with a 0.1 NH4HCO3 (pH 8.0) digesting buffer. The beads were then resuspended in 14 ml of the digest buffer, mixed, and transferred into a beaker with osteochondral plugs. The beaker was then placed on an orbital shaker at 37° C. for 60 minutes.
During the incubation period, the beaker was taken out of the incubator every 15 minutes, sonicated for 2 minutes at 37° C., and returned back to the orbital shaker in the incubator. After 60 minutes of incubation and agitation, the osteochondral plugs were removed from the trypsin bead solution and placed individually in a clean 15 ml conical tube with cartilage cap facing down. The osteochondral plugs were spun at 400 rcf for 10 minutes to remove the excessive fluid.
Then the osteochondral plugs were transferred into a clean sterile beaker and incubated with 30 ml of DMEM supplemented with 10% heat inactivated FBS or human serum for 15 minutes to inactivate the trypsin activity. This trypsin inactivation step was repeated twice with fresh DMEM supplemented with 10% heat inactivated FBS or human serum. Next, the osteochondral plugs were washed with phosphate buffered saline three times, and placed individually in a clean 15 ml conical tube with the cartilage cap facing down. The osteochondral plugs were spun at 400 rcf for 10 minute to remove excessive fluid.
Example 15 Bioactive Growth Supplements Coating on an Osteochondral PlugCarboxylic acid groups of Heparin (sodium alt, 170 USP units/mg, Sigma Aldrich) were activated with EDC (Sigma Aldrich) and NHS (Sigma Aldrich). Ten milligrams of heparin was activated with 10 mg EDC/6 mg NHS in 5 ml of 0.05 M 2-morpholinoethnesulfonic acid (MES) buffer (pH 5.6) for 10 minutes at 37° C. A straight cylindrical osteochondral plug (7 mm in diameter and 10 mm in length) was immersed in the activated heparin solution and shaken at 200 rpm on an orbital shaker at ambient temperature. After 4 hours of reaction, the osteochondral plug was rinsed in 0.05 MES buffer and pH 7.4 phosphate-buffered saline (PBS) three times.
In order to induce chondrogenesis, the bone portion of the heparin immobilized osteochondral plug (5) was fastened onto a plate (288) (
The TGF-β coated osteochondral plug was removed from the plate and transferred into a container (290) that contained PDGF-bb in PBS solution (0.2 mg/ml) (
Recellularization of Osteochondral Plug In Situ with Bone Marrow
A devitalized osteochondral plug with a slot, such as the plug (35) in
Recellularization Hyaline Cartilage Disc In Situ with Chondrocyte
Autologous or allogeneic chondrocytes were isolated from non-load bearing femoral condyle and propagated in vitro in culture media that was composed of Dulbecco's Modified Essential Medium (DMEM) supplemented with 10% FBS, non-essential amino acid, 40 μg/ml proline, and antibiotics (100 U/ml penicillin and 100 μg/ml streptomycin, Invitrogen) for between 3-5 passages. A devitalized cartilage disc stored in a vacuum sealed bag was retrieved and rinsed with isotonic saline. The cartilage disc has a bore in the center, and the depth of which reaches the middle region along the depth. Cultured chondrocytes were trypsinized from the culture flask and suspended in culture media supplemented with 50 μg/ml ascorbate at 10×106 cell/ml density. The devitalized human hyaline cartilage disc was mixed with the 1.5 ml of the cell suspension in a 2 ml tube on a rotator located in an incubator or water bath. The cartilage and the autologous chondrocyte suspension were spun to promote further cell attachment. In addition, the demineralized bone matrix was then mixed with the chondrocyte at 1:1 ratio (volume:volume). Next, the demineralized bone matrix and chondrocyte mixture was inserted into the bore in the cartilage disc. The in situ recellularized cartilage disc was ready to be implanted. The amount of cell attachment and cell viability were then analyzed.
Example 18Recellularization Fibrocartilage Cartilage Slices In Situ with Allogeneic Stromal Cells from Adipose Tissue
Adipose tissue was obtained from a donor. The adipose tissue was rinsed with Hanks' balanced salt solution containing antibiotics (100 U/ml penicillin and 100 U/ml streptomycin) and 2.5 μg/ml amphotericin B. To isolate stromal cells, the adipose tissue was digested for 2 hours on a shaker at 37° C. in HBSS containing 0.2% collagenase (Sigma, St Louis, Mo.) and centrifuged at 1200 rcf for 10 minutes to obtain a high-density cell pellet. The cell pellet was re-suspended in red blood cell lysis buffer for 10 min at room temperature. The stromal cell pellet was collected by centrifugation, as described above, and re-suspended in a chondrogenic media, which was composed of DMEM (Invitrogen), 10% serum, 10 ng/ml TGF-β1, 1% ITS (10 μg/ml insulin, 5.5 μg/ml transferrin, 5 ng/ml selenium, 0.5 mg/ml BSA, 4.7 μg/ml linoleic acid; Sigma;), 50 μg/ml ascorbate-2-phosphate, 40 μg/ml proline, 100 μg/ml pyruvate, and 100 U/ml penicillin and 100 μg/ml streptomycin (all from Invitrogen) at a cell density of 2×106/ml.
Devitalized human fibrocartilage slices stored in a vacuum sealed bag was retrieved and rinsed with isotonic saline. Each individual slice of cartilage from the same package was placed in each well of the 24-well plate. Optionally, a cloning cylinder with grease was place on top of the cartilage slice to create a seal at the peripheral. Stromal cells from adipose tissue were seeded on top of the cartilage slice within the cloning cylinder. The whole plate was centrifuged at 400 g for 5 min to facilitate the cell attachment. The cartilage slices are bonded between adjacent slices using a bonding agent and stack together. Then, the in situ recellularized cartilage slices were ready for implantation. The amount of cell attachment and cell viability were analyzed.
Example 19Recellularization Hyaline Cartilage Slices In Situ with Allogeneic Stromal Cells from Fibrous Synovium
Fibrous synovium was harvested from the inner side of the lateral joint capsule, which overlays the noncartilage areas of the lateral condyles of the femur from cadaver donors. The tissue was minced to pieces with a surgical blade, washed thoroughly with phosphate buffered saline (PBS), and digested in a collagenase solution (3 mg/ml collagenase D; Roche Diagnostics, Mannheim, Germany) in α-minimum essential medium (Invitrogen, Carlsbad, Calif.) at 37° C. After 3 hours, digested cells were filtered through a 70-μm nylon filter (Becton Dickinson, Franklin Lakes, N.J.). Nucleated cells from the tissues were plated at 103 cells/cm2 in a T-75 flask and cultured in DMEM, 10% FBS, 100 U/ml penicillin and 100 μg/ml streptomycin (all from Invitrogen), and 1 ng/mL basic fibroblast growth factor (bFGF) for 14 days before any passages. The same seeding density and media was kept for future passages. Then, passage 3 stromal cells were trypsinized and suspended in chondrogenic media, which was composed of DMEM (Invitrogen), 10% serum, 10 ng/ml TGF-β1, 1% ITS (10 μg/ml insulin, 5.5 μg/ml transferrin, 5 ng/ml selenium, 0.5 mg/ml BSA, 4.7 μg/ml linoleic acid; Sigma;), 50 μg/ml ascorbate-2-phosphate, 40 μg/ml proline, 100 μg/ml pyruvate, and 100 U/ml penicillin and 100 μg/ml streptomycin (all from Invitrogen) at a cell density of 2×106/ml.
Devitalized human hyaline cartilage slices stored in a vacuum sealed bag was retrieved and rinsed with isotonic saline. Each individual slice of cartilage from the same package was placed in each well of the 24-well plate. One milliliter of the stromal cell suspension was added in each well of the 24-well plate. The plate was placed on a shaker and kept at 37° C. until implantation. Optionally, the whole plate was centrifuged at 400 g for 5 min to facilitate cell attachment. Then, the in situ recellularized cartilage slices were ready for implantation. The amount of cell attachment and cell viability were analyzed.
Example 20 Recellularization In Vivo in MuscleA devitalized rabbit osteochondral plug stored in a vacuum sealed bag is retrieved and rinsed with isotonic saline. The devitalized cartilage graft is implanted in a muscle pouch of a nude mouse for 3 months. Then the cartilage disc is retrieved from the muscle, the excessive fibrous tissue surrounding the recellularized cartilage graft is trimmed off, and rinsed with isotonic saline. The in vivo recellularized rabbit osteochondral plug is analyzed for cellular infiltration by immunostaining.
Example 21 Recellularization In Vivo in a Fat PadA devitalized human hyaline cartilage disc without subchondral bone attached and stored in a vacuum sealed bag is retrieved and rinsed with isotonic saline. The devitalized cartilage graft is implanted in the epididymal fat pad of a nude mouse for 3 months. Then the cartilage disc is retrieved from the fat pad, trimmed off the excessive fibrous tissue surrounding the recellularized cartilage graft, and rinsed with isotonic saline. The in vivo recellularized cartilage disc is analyzed for cellular infiltration by immunostaining.
Example 22Recellularization of Osteochondral Plug In Vitro with Allogeneic Stromal Cells from Synovium
A devitalized human osteochondral plug stored in a vacuum sealed bag is retrieved and rinsed with isotonic saline. Each individual osteochondral plug is placed in a 15 ml conical tube with a custom made cap that is connected to an air/gas filter. Allogeneic stromal cells from synovium, as illustrated in Example 19, are suspended in Dulbecco's Modified Essential Medium (DMEM) supplemented with 10% FBS, and antibiotics (100 U/ml penicillin and 100 μg/ml streptomycin, Invitrogen) at a density of 2×106 cells/ml, and added into the tube to immerse the entire osteochondral plug. Then, the tube is placed on a roller, transferred into an incubator, and cultured for 24 hours. Optionally, the cell suspension and the osteochondral plug are centrifuged to facilitate cell attachment. After 24 hours of culture on a roller, the osteochondral plug is transferred into a bioreactor as illustrated in
Then, the cartilage cap is placed within a confining ring (204) and sandwiched between a top porous platens (226) made of porous titanium and a bottom porous ring (241) made of cancellous bone. The entire osteochondral plug is supported by the supporting ring (248) and compressed with a loading shaft connected to a damping spring. The cartilage cap is placed within the top well, while the bone portion is placed in the bottom well of the bioreactor. The culture media in the top well of the bioreactor is chondrogenic media, which is composed of DMEM (Invitrogen), 10% serum, 10 ng/ml TGF-β1, 1% ITS (10 μg/ml insulin, 5.5 μg/ml transferrin, 5 ng/ml selenium, 0.5 mg/ml BSA, 4.7 μg/ml linoleic acid; Sigma;), 50 μg/ml ascorbate-2-phosphate, 40 μg/ml proline, 100 μg/ml pyruvate, and 100 U/ml penicillin and 100 μg/ml streptomycin. The culture media in the bottom well of the bioreactor is osteogenic, and is composed of DMEM (Invitrogen), 10% serum, 100 nM dexamethasone, 10 mM β-glycerophosphate, 50 μg/ml ascorbate-2-phosphate (Sigma), and antibiotics (100 U/ml penicillin and 100 μg/ml streptomycin, Invitrogen). The compressive stress is cycled between 0-6 MPa that is controlled by the load cell and the movement of the loading shaft through a computer. The entire bioreactor is fit into an incubator. The media is circulated between the bioreactor and two media reservoirs that are pumped with filtered 5% CO2 in air. The cyclic compression is conducted for 8 hrs per day. After 4 weeks of culture, the cartilage graft is ready to be transplanted. The cell morphology, viability, extracellular matrix synthesis are analyzed.
Example 23Recellularization of Osteochondral Plug In Vitro with Allogeneic Stromal Cells from Adipose Tissue, Create Contour, Load Opposing Plugs with Loading Shaft
Two devitalized human osteochondral plug with gaps, as illustrated in
After 24 hrs of culture on a roller, two osteochondral plugs are transferred into a bioreactor as illustrated in
Recellularization of Costal Cartilage Disc In Vitro with Chondrocytes, Cultured Under Fluid Pressure
Autologous chondrocytes isolated from recipient's non-load bearing femoral condyle or from a allogeneic source were propagated in vitro in culture media that was composed of Dulbecco's Modified Essential Medium (DMEM) supplemented with 10% FBS, non-essential amino acid, 40 μg/ml proline, and antibiotics (100 U/ml penicillin and 100 μg/ml streptomycin, Invitrogen) for between 3-5 passages. A devitalized costal cartilage disc stored in a vacuum sealed bag was retrieved and rinsed with isotonic saline. Cultured autologous chondrocytes were trypsinized from the culture flask and suspended in culture media supplemented with 50 μg/ml ascorbate at a density of 10×106 cell/ml. The devitalized cartilage disc was mixed with 1.5 ml of cell suspension in a 2 ml tube on a thermal mixer at 37° C. for about 1 hour. Then, the cartilage disc was transferred into a confining ring that had a porous platen made of cancellous bone at the bottom and was on top of another porous platen as illustrated in
Recellularization of Hyaline Cartilage Slices In Vitro with Allogeneic Stromal Cells from Synovium with Fluid Pressure
Allogeneic stromal cells from synovium, as illustrated in Example 19, were suspended in chondrogenic media, which was composed of DMEM (Invitrogen), 10% serum, 10 ng/ml TGF-β1, 1% ITS (10 μg/ml insulin, 5.5 μg/ml transferrin, 5 ng/ml selenium, 0.5 mg/ml BSA, 4.7 μg/ml linoleic acid; Sigma;), 50 μg/ml ascorbate-2-phosphate, 40 μg/ml proline, 100 μg/ml pyruvate, and 100 U/ml penicillin and 100 μg/ml streptomycin. Devitalized human hyaline cartilage slices, stored in a vacuum sealed bag, were retrieved and rinsed with isotonic saline. Each individual slice of cartilage from the same package was placed in each well of a 24-well plate. Optionally, a cloning cylinder with grease was placed on top of the cartilage slice to create a seal at the peripheral. Allogeneic stromal cells from synovium, suspended at 2×106 cells/ml, were seeded on top of the cartilage slice within the cloning cylinder. The whole plate was centrifuged at 400 g for 5 min to facilitate the cell attachment. Each individual cell-seeded slice was transferred in to a confining ring that had a porous platen made of cancellous bone at the bottom and was on top of another porous platen as illustrated in
Recellularization of Hyaline Cartilage Slices In Vitro with Allogeneic Stromal Cells from Bone Marrow to Create a Contour Using Air Pressure
Human allogeneic bone marrow stromal cells (BMSCs) were isolated, cultured, expanded and used for recellularization. Frozen allogeneic whole bone marrow obtained from a commercial source was quickly thawed, washed, counted, and suspended in Dulbecco's modified Eagle medium (DMEM), 10% serum, 0.1 mM nonessential amino acids, antibiotics (100 U/ml penicillin and 100 μg/ml streptomycin, Invitrogen) and 1 ng/mL basic fibroblast growth factor (bFGF). The stromal cells were cultured in T-75 flask with cell density of 103/ml for 3 hrs to allow adherent cells to attach. Then the non-adherent cells were washed out with DMEM. The adherent cells were cultured until near confluence. Passage 3 BMSCs were trypsinized and suspended in chondrogenic media, which was composed of DMEM (Invitrogen), 10% serum, 10 ng/ml TGF-β1, 1% ITS (10 μg/ml insulin, 5.5 μg/ml transferrin, 5 ng/ml selenium, 0.5 mg/ml BSA, 4.7 μg/ml linoleic acid; Sigma;), 50 μg/ml ascorbate-2-phosphate, 40 μg/ml proline, 100 μg/ml pyruvate, and 100 U/ml penicillin and 100 μg/ml streptomycin.
Devitalized human hyaline cartilage slices, without subchondral bone attached and stored in a vacuum sealed bag, were retrieved and rinsed with isotonic saline. Each individual slice of cartilage, from the same package, was placed in each well of the 24-well plate. Optionally, a cloning cylinder with grease was place on top of the cartilage slice to create a seal at the peripheral. Passage 3 BMSCs, suspended at 2×106 cells/ml, were seeded on top of the cartilage slice within the cloning cylinder. The whole plate was centrifuged at 400 g for 5 min to facilitate cell attachment. The BMSC seeded slices were further culture in a 24-well plate for another 24 hours. Each individual cell-seeded slice was then transferred into a confining ring that had a convex porous platen made of cancellous bone at the bottom and was on top of another porous platen as illustrated in
Recellularization of Costal Cartilage Slices and Bone Plug (to Form Composite Graft) In Vitro with Allogeneic Stromal Cells from Synovium, No Combine Culture
Cartilage slices isolated from cadaver costal cartilage, are disinfected, cleaned, devitalized, and recellularized with allogeneic stromal cells from synovium and cultured under mechanical stimuli as illustrated in Example 25 to form a coherent stack of cartilage slices. Parallel to the cartilage slice culture, a hollow cylindrical bone plug (with same outer diameter as the cartilage discs and a center hole in the middle), cleaned, disinfected, freeze dried and sterilized, is soaked in DMEM for 30 min. Allogeneic stromal cells from synovium, suspended at a density of 2×106 cells/ml, are mixed with the bone plug on a thermal mixer overnight at 37° C. On the second day, a highly porous calcium phosphate, obtained from a commercial source, is mixed with the stromal cell suspension. The mixture is inserted into the center of the hollow cylindrical plug. The entire bone plug is further cultured in a roller bottle or under mechanical compression similar to the compression of osteochondral plug as illustrated in Example 22 using osteogenic culture media. The media is composed of DMEM (Invitrogen), 10% serum, 100 nM dexamethasone, 10 mM β-glycerophosphate, 50 μg/ml ascorbate-2-phosphate (Sigma), and antibiotics (100 U/ml penicillin and 100 μg/ml streptomycin, Invitrogen). After 4 weeks of parallel culture of cartilage discs and the bone plug, the grafts are retrieved from corresponding bioreactors and are ready for transplantation. The cell morphology, viability, extracellular matrix synthesis are analyzed.
Example 28Recellularization of Menisci Cartilage Slices and Bone Plug (to Form Composite Graft) In Vitro with Allogeneic Stromal Cells from Synovium, Combine Cultured Under Loading with Loading Shaft
Cartilage slices isolated from cadaver menisci, are disinfected, cleaned, devitalized, and recellularized with allogeneic stromal cells from synovium and cultured under mechanical stimuli as illustrated in Example 25 to form a coherent stack of cartilage slices. Parallel to the cartilage slice culture, a hollow cylindrical bone plug (with same outer diameter as the cartilage discs and a center hole in the middle), cleaned, disinfected, freeze dried and sterilized, is soaked in DMEM for 30 minutes. Allogeneic stromal cells from bone marrow, suspended at a density of 2×106 cells/ml, are mixed with the bone plug on a thermal mixer over night at 37° C. On the second day, demineralized bone matrix, from the same donor as the bone plug, is mixed with the stromal cell suspension and the mixture is inserted into the center of the hollow cylindrical bone plug. The entire bone plug is further cultured in a roller bottle or under mechanical compression similar to the compression of osteochondral plug as illustrated in Example 22 using osteogenic culture media. The media is composed of DMEM (Invitrogen), 10% serum, 100 nM dexamethasone, 10 mM β-glycerophosphate, 50 μg/ml ascorbate-2-phosphate (Sigma), and antibiotics (100 U/ml penicillin and 100 μg/ml streptomycin, Invitrogen). After 1 weeks of parallel culture of cartilage discs and the bone plug, the grafts are retrieved from corresponding bioreactors and transferred into another bioreactor as illustrated in
A devitalized rabbit osteochondral plug, recellularized in vivo as illustrated in Example 20, is used for implantation. The osteochondral plug is step cylindrical and has one slot as shown in plug (35) in
Next, part of the crushed tissue is inserted back into the bore in the recipient joint to fill the gap between the bore and the bone portion of the step cylinder. The osteochondral plug is transferred to the blind bore and pushed slight until interference with the surrounding cartilage tissue. A needle connected to an insertion device is inserted through the cartilage cap. A vacuum device is engaged to remove the air/gas and fluid trapped within the bore and forced the osteochondral plug into the blind bore. After the graft is properly inserted for 2-10 minutes, the photoactivated dye is activated by a laser with 457 nm wave length as illustrated in
Implant Cartilage Disc from Menisci
A devitalized rabbit cartilage disc, isolated from menisci, is crafted to star-shaped right before implantation and recellularized in situ as in Example 17. Both knee joints of a New Zealand white rabbit are exposed through a medial parapatellar longitudinal incision. The capsule is incised, and the medial femoral condyle exposed. With the knee maximally flexed, a first full-thickness bore, 3 mm in diameter and 3 mm in depth, is created in the center of the condyle using a drill with 3 mm outside diameter. A stop is mounted on the drill bit to insure the 3 mm depth of the bore. Then a star-shaped second bore is created only at the cartilage portion of the first bore, using a custom designed coring device as illustrated in
Bone filler is made by mixing the freeze dried demineralized bone matrix with the wet homogenized fascia at 1:1 ratio (by weight). Bone filler is packed into the bone portion of the first bore that is created at the defect site to provide support for the cartilage. The cartilage disc is transferred to the blind bore, fit into the star-shaped bore, and pushed slightly until interference with the surrounding cartilage tissue. Next, a needle connected to an insertion device is inserted through the cartilage disc. A vacuum device is engaged to remove the air/gas and fluid trapped within the blind bore and forces the cartilage disc into the blind bore.
After the graft is properly inserted for 2 minutes, the photoactivated dye is activated by a laser as illustrated in
Both knee joints of a New Zealand white rabbit are exposed through a medial parapatellar longitudinal incision. The capsule is incised, and the medial femoral condyle exposed. With the knee maximally flexed, a partial-thickness bore, 3 mm in diameter and broke the tide mark in depth, is created in the center of the condyle using a drill with 3 mm outside diameter. A stop is mounted on the drill bit to insure the depth of the bore is slightly deeper than the cartilage tissue depth (˜1 mm). All debris is removed from the defect with a curette and the edge carefully cleaned with a scalpel blade. A bore is created on the opposing leg and remained untreated to serve as a control. Devitalized rabbit cartilage slices, of 250 μm thickness, are seeded with allogeneic stromal cells in situ as illustrated in Example 19, and punched to 3 mm diameter. The bore on the treated side is filled with 0.1% riboflavin (10 mg riboflavin 5-phosphate in 10 ml 20% dextran-T-500) supplemented with 5 μM lycopene (Sigma) for 5 minutes to stain the cartilage tissue. Meanwhile, the circumferential area of each of the cartilage slices is treated with the same riboflavin solution. After staining with the photoactive dye, riboflavin is removed from the bore. Each individual cartilage slice is transferred, pushed into the bore against the subchondral bone, and the slices are stacked together until reach the same height as the surrounding tissue. The cartilage slices are boned between adjacent slices using a bonding agent made of MATRIGEL® and genipin. After the graft is properly inserted, the photoactivated dye is activated by two ultraviolet A diodes as illustrated in
Implant Cartilage Slices with Bone Plug and Calcium Phosphate Composite Cylinder
Both knee joints of a New Zealand white rabbit are exposed through a medial parapatellar longitudinal incision. The capsule is incised, and the medial femoral condyle exposed. With the knee maximally flexed, a full-thickness bore, 3 mm in diameter and 3 mm in depth is created in the center of the condyle using a drill with 3 mm outside diameter. A stop is mounted on the drill bit to insure the 3 mm depth of the bore. All debris is removed from the defect with a curette and the edge carefully cleaned with a scalpel blade. A bore is created on the opposing leg and remained untreated to serve as a control. Devitalized rabbit cartilage slices, of 250 μm thickness, are seeded with allogeneic stromal cells, stacked and cultured to form a viable coherent cartilage graft as illustrated in Example 25, and punched to 3 mm diameter. A bone plug filled with porous tri-calcium phosphate and cultured as illustrated in Example 27 is trimmed to the length of the bone portion of the bore at the defect site. The bore on the treated side is filled with 0.1% riboflavin (10 mg riboflavin 5-phosphate in 10 ml 20% dextran-T-500) supplemented with 5 μM lycopene (Sigma) and 5% genipin for 5 minutes to stain the cartilage tissue. Meanwhile, the circumferential area of each of the cartilage slices is treated with the same riboflavin and genipin solution.
After finishing staining with the photoactive dye and crosslinking agent, riboflavin and genipin solution is removed from the bore. The bone plug is inserted into the bore first. Then the stack of cartilage slices is transferred to the bore, fit into the bore, and pushed slight until reaching the same height as the surrounding tissue. Then, the photoactivated dye is activated by two ultraviolet A diodes as illustrated in
Implant Cartilage Curls with a Cartilage Disc
Both knee joints of a New Zealand white rabbit are exposed through a medial parapatellar longitudinal incision. The capsule is incised, and the medial femoral condyle exposed. With the knee maximally flexed, a full-thickness bore, 3 mm in diameter and 3 mm in depth, is created in the center of the condyle using a drill with 3 mm outside diameter. A stop is mounted on the drill bit to insure the 3 mm depth of the bore. All debris is removed from the defect with a curette and the edge carefully cleaned with a scalpel blade. A bore is created on the opposing leg and remained untreated to serve as a control. The bore on the treated side is filled with 0.1% Rose Bengal in collagen solution supplemented with 5 μM lycopene (Sigma Aldrich) for 5 minutes to stain the cartilage tissue. Meanwhile, the circumferential area of the rabbit cartilage disc is treated with the same Rose Bengal solution. After finishing staining with the photoactive dye, the bore in the bone portion is rinsed with isotonic saline.
Next, devitalized rabbit cartilage curls are mixed with freeze dried rabbit demineralized bone matrix (v/v=1:1). Bone marrow withdraw from the same rabbit is used to hydrate the cartilage and DBM mixture. The hydrated cartilage and DBM mixture is packed into the bottom portion of the bore to about 2 mm in depth. The cartilage disc is transferred to the bore, fit into the bore, and pushed slightly until interference with the surrounding cartilage tissue. A needle connected to an insertion device is inserted through the cartilage disc. A vacuum device is engaged to remove the air/gas and fluid trapped within the blind bore and forces the cartilage disc into the blind bore.
After the graft is properly inserted, the photoactive dye is activated by a laser as illustrated in
Claims
1. A shaped cartilage matrix isolated from a human or animal, comprising cartilage which is crafted to facilitate disinfection, cleaning, devitalization, recellularization, and integration after implantation; and wherein said cartilage matrix is isolated from whole condyles, whole plateaus, hemicondyles, hemiplateaus, femoral heads, phalanges, talus, tibia, fibula, rib, intervertebral discs, menisci, nose, or ear,
- wherein said cartilage matrix is in the form of osteochondral plug;
- wherein said osteochondral plug comprises a cartilage cap and a subchondral bone portion contacted to said cartilage cap with a tidemark at an interface between the cartilage and subschondral bone;
- wherein said osteochondral plug has a straight cylindrical shape, a step cylindrical shape, or a dumbbell shape;
- wherein the subchondral bone portion of said osteochondral plug gaps, bores, slots, or channels extending through the tidemark at the cartilage and subchondral bone interface; and
- wherein said modification facilitates disinfection, cleaning, devitalization, recellularization in vivo, in situ, or in vitro, and integration after implantation.
2. A process for repairing a cartilage defect and implanting a cartilage graft into a human or animal, comprising a. crafting the cartilage matrix of claim 1 into individual grafts; b. disinfecting and cleaning said cartilage graft; c. applying a pretreatment solution to said cartilage graft; d. removing cellular debris using an extracting solution to produce a devitalized cartilage graft; e. implanting said cartilage graft into said cartilage defect with or without an insertion device; and f. sealing the implanted cartilage graft to recipient tissue; wherein said devitalized cartilage graft is recellularized with viable cells to render said tissue vital before or after said implanting; wherein said recellularizing devitalized cartilage graft is carried out in vitro, in vivo, or in situ; and wherein said devitalized cartilage graft is optionally stored between said removing cellular debris and recellularizing steps.
3. A repaired cartilage defect repaired by the process of claim 2.
4. The cartilage matrix of claim 1, wherein said osteochondral plug is crafted to have one or multiple gap(s).
5. The cartilage matrix of claim 1, wherein said osteochondral plug is drilled and/or milled from the bottom of the subchondral bone portion to form one or more channels.
6. The cartilage matrix of claim 1, wherein said osteochondral plug is drilled and/or milled on the cylindrical surface of the subchondral bone portion at the cartilage and subchondral bone interface to form one or more through channels.
7. The cartilage matrix of claim 1, wherein said osteochondral plug is drilled and/or milled on the cylindrical surface of the subchondral bone portion at the cartilage and subchondral bone interface to form one or more slots.
8. The cartilage matrix of claim 1, wherein the circumferential surface area of said cartilage cap on said osteochondral plug is modified to facilitate the integration of graft tissue to a recipient tissue.
9. The cartilage matrix of claim 8, wherein said cartilage cap is crafted to have a star shape or tapered cylindrical shape to maximize the circumferential surface area of said cartilage cap on said osteochondral plug and/or to prevent rotation of said osteochondral plug in the recipient tissue.
10. The cartilage matrix claim 8, wherein said cartilage caps are crafted to increase circumferential surface area by spraying or blasting microparticles or embossing with a straight or non-straight line pattern or cross-line pattern onto the circumferential surface.
11. The cartilage matrix of claim 1, wherein the circumferential surface and/or the superficial surface of said cartilage cap on said osteochondral plug is microperforated to facilitate disinfection, cleaning, devitalization, recellularization in vivo, in situ, or in vitro, and the integration of graft tissue to a recipient tissue.
12. The cartilage matrix of claim 4, wherein said cartilage cap is sectioned off the subchondral bone portion to become a cartilage disc; wherein said cartilage disc has a full or partial depth; wherein said full or partial depth cartilage disc has one or more gaps starting from the deep zone of said cartilage disc; and wherein said gaps end at the deep, middle, or superficial zone of said cartilage cap along the depth direction and do not penetrate the superficial surface of said cartilage disc.
13. The cartilage matrix of claim 5, wherein said cartilage cap is sectioned off the subchondral bone portion to become a cartilage disc; wherein said cartilage disc has a full or partial depth; and wherein said full or partial depth cartilage disc has one or more channels starting from the deep zone of said cartilage disc; and wherein said channels end at the deep, middle, or superficial zone of said cartilage disc along the depth direction and do not penetrate the superficial surface of said cartilage disc.
14. The cartilage matrix of claim 6, wherein said cartilage cap is sectioned off the subchondral bone portion to become a cartilage disc; wherein said cartilage disc has a full or partial depth; and wherein said full or partial depth cartilage disc has one or more through channels that are also parallel to the superficial surface of said cartilage disc and start at the deep zone of said cartilage disc; and wherein said channels occupy portions of the deep and/or middle zone of said cartilage disc along the depth direction and do not occupy the superficial zone of said cartilage disc.
15. The cartilage matrix of claim 7, wherein said cartilage cap is sectioned off the subchondral bone portion to become a cartilage disc; wherein said cartilage disc has a full or partial depth; and wherein said full or partial depth cartilage disc has one or more slots starting at the deep zone of said cartilage disc; and wherein said slots occupy portions of the deep and/or middle zone of said cartilage disc along the depth direction and do not occupy the superficial zone of said cartilage disc.
16. The cartilage matrix of claim 1, wherein said cartilage matrix is sectioned, shaved, or skived into cartilage slices and wherein said cartilage slices are tailored to have circular, square, triangular or star shapes.
17. The cartilage matrix of claim 1, wherein said cartilage matrix is shaved or skived into cartilage curls or flakes in irregular shapes.
18. The cartilage matrix of claim 17, wherein said cartilage curls or flakes are mixed with a carrier.
19. A shaped cartilage matrix isolated from a human or animal, comprising cartilage which is crafted, cleaned, disinfected, and devitalized.
20. A shaped cartilage matrix isolated from a human or animal, comprising cartilage which is crafted, cleaned, disinfected, devitalized, and recellularized.
Type: Application
Filed: Jun 3, 2021
Publication Date: Oct 21, 2021
Applicant: LifeNet Health (Virginia Beach, VA)
Inventors: Silvia Sihui Chen (Derwood, MD), Xiaofei Qin (Virginia Beach, VA), Jingsong Chen (Virginia Beach, VA), Lloyd Wolfinbarger, JR. (Norfolk, VA)
Application Number: 17/338,372
