Study Of Bone Mesenchymal Stem Cells-Seeded Small Instestinal Submucosa For Rabbit Articular Cartilage Repair

Objective The object of this experimental research is to observe the results of using the tissue engineering cartilage to repair the rabbit full cartilage defects , then to provide the foundation for the application of tissue engineering cartilage to repair the full cartilage defects in clinical orthopedics. Methods (1) Bone marrow was harvested from the iliac bone of Janpanese white rabbits. After gradient centrifugation , cultivation, amplification, the 3rd-passaged BMSCs were implanted in six—hole—plate according to a certain proportion and induced by chondrogenic inducers including transforming growth factorbetal, dexamethasone and vitamin C. Chondrocytes were selected and fixed at different time. The features of chondrocytes were identified by CD34,CD44 and collagen types II immunohistochemical assay; (2) After BMSCs were induced for eight days, we seeded the cells on small instestinal submucosa to culture for 48 hours; (3) To form the model of full cartilage defects, articular cartilage of 36 rabbit knee condyle of femur bone were removed by operative means. The rabbit was divided into three groups. The tissue engineering cartilage were transferred into the defects, whereas the cells was seeded on small instestinal submucosa and small instestinal submucosa was implanted in the control group. The third was the control group. The specimens were harvested at 4,8 and 12 weeks after operation, and the ability of chondrogenesis in vivo was investigated by the gross observation, HE stain, Safranine 0 staining and collagen types II immunohistochemical assay. Result According to observation in general and histological examination, BMSCs basically can repair the defects in cartilage, and the reparation tissues are composed of hyaline cartilage and spongy bone . But in the negtive control there are only bad reparation tissue made of fibrous tissue or no neogenesis tissue at all and the defects in the bone and cartilage exist apparently. Conclusion BMSCs can differentiate into chondrocytes in the defect of the joint cartilage, repair the defects of cartilage and regain the normal structure of cartilage.