The Experimental Study Of Repairing Rabbit Meniscus Lesion With Autologous Synovial-Derived Mesenchymal Stem Cells And Small Intestinal Submucosa

The feasibility study of rabbit meniscus repair was evaluated with the use of rabbit autologous synovial-derived mesenchymal stem cells(SMSCs) and pig's small intestinal submucosa(SIS). Synovium cell populations were enzymatically released from the synovial tissue and were expanded in monolayer with serial passages at confluence. Cell clones were obtained by limiting dilution. After the synergic stimulation of such cytokines as BMP-2,TGF-β3 and DEX, the SMSCs were detected by RT-PCR and by histo- and immunohisto-chemistry for the expression of chondrocyte-related maker to confirm the pluropotential cell's entering into the chondrogenic lineage. Subsequently, SIS scaffold was synthesized and SMSCs that had entered into the chondrogenic lineage were added into the porous SIS scaffold. Then, the SMSCs-SIS were implanted in vivo to the menisci-injured rabbit knees as the substitute for the injured meniscus.After 6, 12 weeks postoperation, the implants were evaluated by gross observations and by histo- and immunohisto-chemistry. As a result, the SMSCs-enriched SIS implants underwent inflammation, degradation, SMSCs differentiation and remodeling stages in vivo, and consequently formed a meniscus-like fibrocartilage tissue. The collage I, collage II and S-100 protein were expressed at area of the repaired meniscal tissue by immunohistochemistry. The glycosaminoglycan(GAG) was detected by toluidine blue staining. All above proved the repaired meniscal tissue were chondrocyte-like fibrochondrocytes. On the contrast, the results of control group showed that both SIS implants without SMSCs and no substitute had limited regenerating tissue, further evaluations by histological observations showed no evidence of fibrochondrocytes, and hence these regenerated tissue were fibrous rather than fibrocartilagous.In conclusion, the inducing of rabbit meniscus repair by autologous SMSCs and porous SIS scaffold is proved to be feasible in this study. However, further studies such as improving biomaterial design, evaluating the biomechanical properties of the regenerated tissue and ensuring clinical safety et al. are necessary to enhance the efficiency of the idea.