In vivo chondrogenesis of induced human marrow mesenchymal stem cells in nude mice]

OBJECTIVE: To investigate the feasibility of generating cartilage tissues from human bone marrow mesenchymal stem cells (MSCs) cultured and induced in vitro using tissue engineering technique. METHODS: Human bone marrow MSCs were isolated from the ribs of patients receiving chest surgeries and induced into cartilage cells in serum culture-free medium. The cells were then seeded on perchloroethylene (PCE) as the scaffold material for the formation of cell-PCE composite, which was implanted under the dorsal skin of nude mice. Specimens of the implants were harvested 6 weeks after implantation and subjected to gross morphological observation and histological examination. RESULTS: Gross observation showed subcutaneous lump with considerable tenacity, and histologically, large amount of cartilage cells in clusters were seen to have evolved, in the presence of some scaffold material failing to be degraded, indicating that cartilage formation from the MSCs occurred approximately 6 weeks after the implantation of the induced MSCs. CONCLUSION: Human MSCs can be induced into chondrocytes in vitro, and the MSC-PCE composite possesses the potential to develop into cartilage in nude mice. Human MSCs can therefore be used as the seed cells to construct tissue-engineered cartilage.