RESUMEN
[Objective]To investigate the rlpairing effect on articular cartilage defects by composite of cocultures of autogenic bone marrow-derived mesenchymal stem cells(BMSCs) and chondrocytes with allogenic fully deproteinized bone(FDB),in order to provide basis for optimizing seeding cells resources.[Method]Seeding cells were collected from two-passaged BMSCsand chondroeytes and then cocultured at the rate of 2 to 1.Full thickness articular cartilage defects in the knee joints of rabbits repaired by cocultured cells seeded into allogenic FDB were served as experimental group A,by simple FDB as control group B and by nothing as blank control group C.Repaired tissues were evaluated with macroscopic views,histological scores and immunohistochemistrical stains at 8 and 16 weeks postoperatively.[Result]Chondrocytes cocultured riched in extracellular matrix and proliferated promptly.In A regenerated tissues represented hyaline-like,smoothness and flat.In group B and C,repaired tissues were fiberous and no repaire in group C.Histological scores of experimental group A excelled group B and C with statistically significant differences(P0.05).Immunohistochemistrical stains showed that cells in the zones of repaired tissues were larger in size,arranged columnnedly,riched in type-Ⅱ collagen matrix and integrated satisfactorily with native adjacent cartilages and subchondral bones in the experimental group A at 16 weeks postoperatively.[Conclusion]Cocultures of autogenic BMSCS with chondrocytes can promote proliferation of chondrocytes and production of chondral matrix.Cocultures as seeding cells can save a number of chondrocytes,shorten culturing periods and reduce subcultured times.Cocultures embedded into FDB can repair articular cartilage defects effectively.