去细胞异种神经复合骨髓基质干细胞修复周围神经缺损的实验研究

Acellular xenogeneic nerve repopulated with BMSCs to repair peripheral nerve defects： an experimental study

目的探讨去细胞异种神经（aeellular xenogeneienerve，AxN）复合骨髓基质干细胞（bone marrow stem cells，BMscs）修复周围神经缺损的效果。方法体外培养大鼠BMSCs；取雌性Wistar大鼠60只，随机分为3组，每组20只，建立右坐骨神经10in／n缺损修复模型。A组：BMSCs与AXN复合修复神经缺损；B组：单纯AXN修复神经缺损；C组：自体神经移植组。术后4、12周依次进行干细胞的转归、移植免疫、神经电生理检测、新生神经组织学观察和小腿三头肌肌纤维横径等检测，判断坐骨神经功能恢复情况。结果术后移植物内均可见细胞生长，A、C组细胞数目较多，排列整齐，只有A组S-100免疫组化染色阳性细胞内可见BrdU阳性表达，术后12周再生神经已通过远端缝合口。A组、C组组织学及电生理检测指标均优于B组（P〈0．05），A组与C组差异无统计学意义（P〉0．05）。结论BMSCs作为种子细胞可以在体内存活，并可分化为SCs，其与AXN复合构建组织工程神经修复神经缺损的效果接近于自体神经移植。

Objective To evaluate the outcomes of repairing peripheral nerve defects with aeellular xenogeneic nerve （AXN） repopulated with bone marrow stromal cells （BMSCs）. Methods Rat BMSCs were cultured in vitro. Right sciatic nerve 10 mm defect model was established in 60 female Wistar rats that were randomly divided into 3 groups, with 20 each. The gaps were repaired using one of the following： AXN repepulated with BMSCs （group A）, AXN （group B） and autologous nerve gra~ （group C）. Tissues were harvested 4 and 12 weeks after the operation. The status of BMSCs and axonal regeneration were evaluated by general observation, eleetmphysiologieal examination, gastmenemius muscle fiber measurement, histological observation and scanning electron microscopy （SEAM） observation of the regenerating nerve. Results After transplantation viable eeUs were observed in all the grafts. More ceils were noted in group A and C, whleh were well oriented. BrdU positive expression was seen in S-100 positive cells only in group A. After 12 weeks, regenerating axons had passed the defect. I-Iistologieal and eleetrophysiologieal testing were better in group A and C than in group B （ P 〈 0.05）. No signitleant differenee was detected between group A and C （ P 〉 0.05）. Conclusion BMSCs can survive in the body, and can differentiate into SCs. AXN repepulated with BMSCs leads to comparable results to autologous nerve graft when used to repair nerve defects.