Abstract: Objective To investigate the feasibility of bone marrow mesenchymal stem cells(BMSCs) in vitro cartilage construction and transplantation for repairing large articular cartilage defects in large animals. Methods The cartilage defect model was established by using 7 changfeng hybrid pigs as animal models, and the cartilage defect was repaired by tissue engineered cartilage transplantation with autologous BMSCs in vitro targeted induction for 8 weeks. The pure PGA/PLA material group, the blank control group and the normal cartilage group were set up as control. Six months after operation,gross and histological examinations were carried out. At the same time, the expression levels of the key cytokines such as IGF-1, IL-1β, MMP-13 and TNF-α in synovial fluid were detected before and after operation. The repair effect was evaluated comprehensively. Results Six months after the operation, most of the experimental groups obtained ideal cartilage tissue repair, the general view and histological maturity of the cartilage tissue in the repair area was very close to the normal cartilage tissue. In the test of joint fluid, the expression of IGF-1 in the experimental group was significantly higher than that in the blank control group and PGA group(P <0.05), while the expression levels of IL-1β, MMP-13 and TNF-α were significantly lower than those in the blank control group and PGA group(P<0.05). Conclusion Tissue engineered cartilage constructed by pig’s BMSCs in vitro can effectively repair articular cartilage defects, thus avoiding or delaying the development of osteoarthritis.

Key words: Tissue engineering, Bone marrow mesenchymal stem cells, Articular cartilage defects