Effect Of MSCs In Combination With PRP On Tendon-bone Healing Of ACL Reconstuction

Objective To study the effect of autologous mesenchymal stem cell(MSCS) in combination with platelet rich plasma(PRP) transplantation on tendon-bone healing after anterior cruciate ligament(ACL) reconstruction.Methods peripheral blood harvested from rabbits to obtain MSCs. 24 adult New Zealand rabbits were randomly divided into M,P,PM and C group(n=24). Rabbits in M group were injected with MSCs via thrombin,in P group were injected with PRP via thrombin MP group were injected with a mixture of MSCs,PRP via thrombin, while C group were injected with only sodium hyaluronate. Four rabbits were killed4,8 and 12 weeks after operaton and samples were collected for histological observation of tendon-bone healingResults The primary cells were growing rapidly and closed to the bottom of the culture bottle.The cellular morphologythe was fusiform,and the cytoplasm was translucent. Cultured the cells to the third generation.The cells were colony formation, uniform morphology, neat, vigorous growth. Flow cytometry showed that the detected cells expressed CD29, CD90 positive and the CD11 b, CD34 negative, and the cells cultured in the osteogenic induction medium can differentiation into bone cells, accorded with the identification of MSCs results. M, P and MP group showed that tendon bone are closely connected and a small amount of fibroblast ingrowth in MP group showed the mature cartilage like cells were distributed in the tendon bone interface 4 weeks after the operation. Sharpy’s like fiber could be found in MP, P, M group 8 weeks after the operation and MP group Sharpy like fiber was increased, which in the MP group mature cartilage like cells significantly more than the other two groups. After 12 weeks, M, P, MP group showed a large number of Sharpy like fiberformation, C group only in the twelfth week was found to have Sharpy’s like fibers of only 1 section.Differences of the number of sections that had Sharpy’s like fiber of each group were significant(P<0.05), Differences of the histomorphology Buark score of each group were significant(P < 0.05),. MSCs and PRP can promote tendon to bone interface fibroblasts and collagen fiber hyperplasia and promote the repair of tendon to bone interface, and can improve tendon bone interface stiffness and maximum load capacity, increase the intension of tendon to bone interface.Conclusion MSCs in combination with PRP can promote tendon-to-bone healing,and more effective than that of single factor.