Experimental Study Of Meniscal Repair In Avascular Zone By The Use Of Mscs Induced By BMP-2

Objective:In order to find a better way to repair meniscal defects in avascular zone, MSCs are used as seed cells, BMP-2are used as cytokines,and autologous fibrin glue(FG) are used as matrix in experimental New Zealand rabbits models. In this study,passage and amplification of MSCs are not needed. By the induction of BMP-2, MSCs are converted into fibrochondrocytes in FG to repair meniscal defects in avascular zone. With the repair of meniscal defects, articular cartilage degeneration can be avoided in long term. Maybe some methods can be learned from this experiment in the repair of meniscal defects in avascular zone.Method:In this study,36New Zealand rabbits, which are6-12months old and2-3kg in weight, are used as the animal models and they are divided into2groups randomly. Every group has18rabbits. All the menisci in two sides knees are used and they are made into defect models in avascular zone of the caudomedial part. Fibrin glue(group FG) are used in one side of the group A randomly and no treatment(group NT) are taken in the other side.Also, in group B, fibrin glue and MSCs(group FM) are used in one side randomly and fibrim glue, MSCs and BMP-2(group FMB) are used in the other side. All the specimens are taken in4week,8week and12week after operation.The specimens are prepared for macroscopy, light macroscopy and transm-ission electron microscopy(TEM).Result:1. Macroscpy:Group NT has no evident repair after operation at4week,8 week and12week in its avascular zone. There was a significant difference between group NT and FMB(P<0.05), but compared with group FG and FM, the difference was not significant in statistics(P>0.05). Group FG was repaired better than group NT except group FM and FMB. But, in statistics, the difference was significant only between group FG and FMB(P>0.05). Group FMB was obviously repaired better than other groups in its avascular zone. In statistics, the difference was significant, compared with group NT and FG(P<0.05). Also,at12week, difference was significant between group FMB and FM(P<0.05).2. Light macroscopy: The repair tissue of Group FG was like fiber tissue after operation and there was no cartilage cells in the new tissue. The repair tissue of group FM was fiber tissue and few fibrocartilage cells can be seen. In group FMB, the repair tissue has no significant difference with normal fibrocartilage tissue. The meniscus lesion has been excellently repaired at12week after operation. At12week, toluidine blue staining shows that group FMB is better repaired than the other two groups. There is a significant difference in statistics(P<0.05).3. transmission electron microscopy (TEM): Fibrocar-tilage cell of group FMB has a better appearance than other groups.Conclusion:Fibin glue is a good carrier for mesenchymal stem cells and bone morphogenetic protein. The meniscus lesion could be excellently repaired with FG, MSCs and BMP-2. A new method can be learned from this experiment in the repair of meniscal defects in avascular zone.