骨髓间充质干细胞促进前交叉韧带重建后腱-骨愈合的生物力学研究

Biomechanical study on bone marrow-derived mesenchymal stem cells promoting tendon-bone healing following anterior cruciate ligament reconstruction

目的观察骨髓间充质干细胞（ bone marrow- derived mesenchymal stem cells,，bMSCs）移植对兔前交叉韧带（anteriorcruciateligament，ACL）重建后移植物与骨道愈合的影响。方法选择24只新西兰大白兔，取自体同侧部分腓肠肌腱作为移植物，构建ACL重建模型，双后肢均纳入研究，一侧使用混合bMSCs的纤维蛋白胶包裹移植物（bMSCs组），对侧后肢单纯使用纤维蛋白胶包裹移植物（对照组）。分别于术后2，4，6，8周取材检测腱-骨界面的断裂强度和刚度。结果bMSCs组和对照组腱-骨界面的断裂强度和刚度均随修复时间延长呈上升趋势，其中实验组腱-骨界面的断裂强度和刚度自第6周始明显高于对照组（P〈0．05）。结论bMSCs移植可明显提高兔ACL重建后早期腱-骨界面的断裂强度和刚度，促进移植物与骨道早期愈合。

Objective To observe the effect of bone marrow-derived mesenchymal stem cells （bMSCs） on graft healing within a bone tunnel after anterior cruciate ligament （ACL） reconstruction in rabbits. Methods The study involved 24 New Zealand white rabbits undergone ACL reconstruction with an autologous ipsilateral gastrocnemius tendon graft. Both hindlimbs were included. In one hind- limb, graft coated with fibrin glue compound by bMSCs was employed （bMSCs group）. Whereas in the contralateral hindlimb, graft coated with fibrin glue without cells was employed （control group）. At post- operative 2, 4, 6 and 8 weeks, specimens were harvested to have a biomechanical test of tensile strength and stiffness of tendon-bone interface. Results Tensile strength and stiffness of tendon-bone interface in both experiment and control groups presented a rising trend with the prolong of repair time. In contrast, significantly higher tensile strength and stiffness of tendon-bone interface were observed in experiment group since the 6 weeks （ P 〈 0.05 ）. Conclusion bMSCs transplantation significantly enhances the early tensile strength and stiffness at tendon-bone interface after ACL reconstruction in rabbits and im- proves the graft healing within a bone tunnel.