Engineered osteochondral construct for treatment of articular cartilage defects

• US 20070009610A1
• Filed: 07/07/2006
• Published: 01/11/2007
• Est. Priority Date: 07/11/2005
• Status: Active Grant

• Current Assignee: Musculoskeletal Transplant Foundation
• Original Assignee: Musculoskeletal Transplant Foundation
• Inventors: Syring, Carina
• Granted Patent: US 7,815,926 B2
• Time in Patent Office: Days
• US Class Current: 424/548
• CPC Class Codes: A61K 35/12 Materials from mammals; Compositions comprising non-specified tissues or cells; Compositions comprising non-embryonic stem cells; Genetically modified cells vaccines or medicinal preparations containing antigens or antibodies A61K39/00
• CPC Class Codes: A61K 35/32 Bones; Osteocytes; Osteoblasts; Tendons; Tenocytes; Teeth; Odontoblasts; Cartilage; Chondrocytes; Synovial membrane
• CPC Class Codes: A61L 2430/06 for cartilage reconstruction, e.g. meniscus
• CPC Class Codes: A61L 27/3608 Bone, e.g. demineralised bone matrix [DBM], bone powder
• CPC Class Codes: A61L 27/3654 Cartilage, e.g. meniscus
• CPC Class Codes: A61L 27/3683 subjected to a specific treatment prior to implantation, e.g. decellularising, demineralising, grinding, cellular disruption/non-collagenous protein removal, anti-calcification, crosslinking, supercritical fluid extraction, enzyme treatment
• CPC Class Codes: A61L 27/3817 Cartilage-forming cells, e.g. pre-chondrocytes
• CPC Class Codes: A61L 27/3852 Cartilage, e.g. meniscus
• CPC Class Codes: A61L 27/3895 using specific culture conditions, e.g. stimulating differentiation of stem cells, pulsatile flow conditions
• CPC Class Codes: C12N 2533/18 Calcium salts, e.g. apatite, Mineral components from bones, teeth, shells
• CPC Class Codes: C12N 5/0655 Chondrocytes; Cartilage

Abstract

A method of growing chondrocytes on an allograft cancellous bone structure which had been previously treated by demineralization to form a cartilage repair implant comprises isolating allograft chondrocytes from articular cartilage of a donor other than the patient on which the implant is to be used, cultivating the isolated chondrocytes in a medium to obtain a dedifferentiated fibroblast-like phenotype, placing an at least partially demineralized allograft cancellous bone structure carrier having at least one surface prepared for cell seeding in a culture vessel; adding the cultivated dedifferentiated chondrocytes to a demineralized surface of the cancellous bone structure carrier, and incubating the cancerous bone structure carrier for a period of time of at least 40 days to obtain an implant with a cartilage layer which ranges from about 2 mm to 5 mm n thickness.

Claims

1. A cartilage repair implant for repair of a defect in articular cartilage of a mammal comprising a sterile allograft cancellous bone implant body which has been at least partially demineralized and an overlying cartilage surface which has been formed in vitro on said cancellous bone body by the cultivation of allograft chondrocytes on said cancellous bone body.

2. A cartilage repair implant as claimed in claim 1 wherein said chondrocytes were taken from donors less than 50 years of age.

3. A cartilage repair implant as claimed in claim 1 wherein said chondrocytes were taken from live donors.

4. A cartilage repair implant as claimed in claim 1 wherein said chondrocytes were taken from deceased donors.

5. A cartilage repair implant as claimed in claim 1 wherein said cancellous body has at least one surface demineralized to a depth of about 2 mm

6. A cartilage repair implant as claimed in claim 1 wherein said cancellous body has pores formed therein ranging from 10 to 100 microns in size.

7. A cartilage repair implant as claimed in claim 5 wherein after demineralization a boundary layer is formed between the fully demineralized section and the mineralized section which is about 50 microns in thickness.

8. A cartilage repair implant as claimed in claim 1 wherein said chondrocytes are dedifferentiated chondrocytes.

9. A cartilage repair implant as claimed in claim 1 wherein said chondrocytes form a cartilage surface in layers about 2.0 mm thick.

10. A cartilage repair implant for repair of a defect in articular cartilage of a mammal comprising a sterile allograft cancellous bone implant body which has been at least partially demineralized and has an overlying cartilage surface of at least 2.0 mm formed on at least one surface of said cancellous bone body by the growth of allograft chondrocytes on said allograft cancellous bone body.

11. A method of growing chondrocytes on an allograft implant which has been previously treated by demineralization comprising the steps of:

(a) isolating chondrocytes from articular cartilage,

(b) cultivating the isolated chondrocytes in a medium to obtain dedifferentiated fibroblast-like phenotype,

(c) placing a cancellous bone structure carrier having at least one surface demineralized and prepared for cell seeding in a culture vessel;

(d) adding the cultivated chondrocytes to a demineralized surface of the cancellous bone structure carrier, and

(e) incubating the cancellous bone structure carrier for a period of time to obtain a cartilage formation on the cancellous bone structure which is at least 2 mm in thickness.

12. A method of growing chondrocytes on an allograft implant as claimed in claim 11 wherein said chondrocytes were taken from donors less than 50 years of age.

13. A method of growing chondrocytes on an allograft implant as claimed in claim 11 wherein said chondrocytes were taken from live donors.

14. A method of growing chondrocytes on an allograft implant as claimed in claim 11 wherein said chondrocytes were taken from deceased donors.

15. A method of growing chondrocytes on an allograft implant as claimed in claim 11 wherein said chondrocytes of said cartilage formation are a multilayer chondrocyte growth

16. A method of growing chondrocytes on an allograft bone implant which had been previously treated by demineralization comprising the steps of:

(a) isolating allograft chondrocytes from articular cartilage of a donor other than the patient on which the implant is to be used,

(b) cultivating the isolated chondrocytes in a medium to obtain dedifferentiated fibroblast-like phenotype,

(c) placing an at least partially demineralized allograft cancellous bone structure carrier having at least one surface prepared for cell seeding in a culture vessel;

(d) adding the cultivated dedifferentiated chondrocytes to a demineralized surface of the cancellous bone structure carrier, and

(e) incubating the cancellous bone structure carrier for a sufficient period of time to allow formation of a cartilage layer on the cancellous bone structure which ranges from about 2 mm to 5 mm n thickness.

17. A method of growing chondrocytes on an allograft bone implant which had been previously treated by demineralization as claimed in claim 16 wherein said donor is younger than 50 years of age.

18. A method of growing chondrocytes on an allograft bone implant which had been previously treated by demineralization as claimed in claim 16 wherein said donor is deceased.

19. A method of growing chondrocytes on an allograft bone implant which had been previously treated by demineralization comprising the steps of:

(a) isolating allograft chondrocytes from articular cartilage of a donor to obtain a suspension of chondrocytes,

(b) expanding the isolated chondrocytes in a medium to obtain dedifferentiated chondrocytes phenotype,

(c) placing an at least partially demineralized allograft cancellous bone structure carrier having at least one surface prepared for cell seeding in a culture vessel;

(d) adding the cultivated dedifferentiated chondrocytes to a demineralized surface of the cancellous bone structure carrier, and

(e) incubating the cancellous bone structure carrier for a period of time of at least 40 days to obtain a cartilage layer which ranges from about 2 mm to 5 mm n thickness.

20. A method of growing chondrocytes on an allograft bone implant as claimed in claim 19 wherein said medium in step (b) is fetal calf serum.