OBJECTIVESTo induce autologous bone marrow derived mesenchymal stem cell (aMSC) into chondrocyte, and to confirm the effects of 3 dimensional (3D) dynamic inducing in vitro and their long-term animal model repairing in vivo.

METHODSaMSC were separated from rabbits bone marrow aspirates, then respectively experienced 3D dynamic inducing in alginate drops in modified rotating wall bioreactor culture or in two dimensional (2D) inducing (culture flask) for 10 d. The induced cells were harvest and then mixed with fibrin sealant (FS) to repair rabbit knee femoral trochlea cartilage defects model. After 8, 12, 24, 48 weeks animals were euthanized. Gross appearance, histological appearances were examined.

RESULTSFlask culture groups showed a little chondrocyte differentiation, 3D inducing group showed obviously chondrocyte differentiation, improved collagen II and proteoglycan production. For 3D inducing ones in vivo, the cartilage defects were smoothly repaired by white translucent hard tissue with obvious hyaline-like cartilage histological appearance after 8, 12 weeks, and the defects boundary were hard to be identified with hyaline like cartilage with sustained histological appearance and score after 24, 48 weeks. For 2D ones in vivo, the cartilage defects were smoothly repaired after 8 weeks by hyaline like cartilage which showed accelerated degeneration after 24 weeks and lose cartilage performance completely after 48 weeks.

CONCLUSIONS3D dynamic inducing may assist aMSC on differentiating into chondrocyte, improve its long-term in vivo repairing effects, and enlighten its further applications in tissue engineering cartilage.