无细胞神经移植物复合骨髓间充质干细胞修复大鼠坐骨神经缺损

背景:作者前期试验已成功制备了天然可生物降解的无细胞神经移植物并证明其可促进周围神经再生.目的:无细胞神经移植物复合骨髓间充质干细胞构建组织工程人工神经并观察其修复大鼠坐骨神经缺损促进运动功能恢复的效果.设计、时间及地点:随机对照动物实验,于2008-06/2009-02在辽宁医学院附属第一医院医学组织工程实验室完成.材料:180～200 g成年健康雄性Wistar大鼠,用于制备无细胞神经移植物,100～120 g成年健康雄性Wistar大鼠,用于制备骨髓间充质干细胞,将骨髓间充质干细胞植入并与无细胞神经支架联合培养构建组织工程人工神经.方法:180～200 g成年健康雄性SD大鼠60只构建坐骨神经15 mm缺损模型,随机分成3组,每组20只.①实验组采用组织工程人工神经桥接大鼠坐骨神经缺损.②空白对照组采用组织工程神经支架桥接大鼠坐骨神经缺损.③自体神经对照组采用自体神经移植桥接大鼠坐骨神经缺损.主要观察指标:术后12周通过大体观察、电生理检测、组织学和小腿三头肌湿质量等方法分析评价运动功能恢复情况.结果:①术后12周,实验组大鼠手术侧足趾可以分开,并且可以支撑着地;实验组大鼠再生神经传导速度与自体神经对照组相比,差异无显著性意义.②术后12周,实验组组织化学染色可见腓肠肌内有呈AchE阳性的运动终板整齐地排列于腓肠肌的中上部形成终板带,经结合镀银染色后可见再生的神经束及发出的分支与运动终板相连.③实验组与自体神经对照组胫骨前肌湿质量比差异无显著性意义.结论:无细胞神经移植物复合骨髓间充质干细胞桥接大鼠坐骨神经缺损具有促进其运动功能恢复的作用.

Repairing rat sciatic nerve defects with the compound of acellular nerve graft and bone marrow mesenchymal stem cells

BACKGROUND: Previous studies have successfully prepared the natural and biologically degraded acellular nerve graft and have proved the effect of promoting neural regeneration.OBJECTIVE: To construct tissue engineered artificial nerve with acellular nerve graft and bone marrow mesenchymal stem cells, and to observe the effect of promoting motor functional recovery and repairing rat sciatic nerve defects. DESIGN, TIME AND SETTING: Randomized control animal experiment was performed in the Medical TIssue Engineering Laboratory of the First Affiliated Hospital of Liaoning Medical University between June 2008 and February 2009. MATERIALS: Wistar adult healthy male rats weighing 180-200 g were used to prepare acellular nerve graft, while Wistar adult healthy male rats weighing 100-120 g were used to prepare bone marrow mesenchymal stem cells. Tissue engineered artificial nerve was produced with acellular nerve graft co-cultured with bone marrow mesenchymal stem cells. METHODS: Sixty Wistar adult healthy male rats weighing 180-200 g were induced sciatic nerve defect models, 15 mm long. SD rats were divided into three groups at random with 20 animals in each group. ①Experiment group: Rat sciatic nerve defects were bridged with tissue engineered artificial nerve. ②Blank control group: Rat sciatic nerve defects were bridged with tissue engineered nerve scaffold. ③Autologous nerve control group: Rat sciatic nerve defects were bridged with autologous nerve graft. MAIN OUTCOME MEASURES: At 12 weeks postoperation, the recovery of motor function was evaluated with gross observation, electrophysiology, histological observation and triceps surae wet weight.RESULTS: ①At 12 weeks postoperation, the toes at the operation side could separate and supported to the ground in the experiment group; there was no significant difference in the regenerated nerve conduction velocity between experimental group and autologous nerve graft group. ②At 12 weeks postoperation, histochemical stain results showed AchE-positive motor end-plate arranged regulady in the middle and superior part of gestrocnemius muscle to form end-plate zone in the experiment group. By use of silver staining, the regenerated nerve tract and the emergent branch were shown to be connected with motor end-plate.③There was no significant difference in the tibialis anterior muscle wet weight between experimental group and autologous nerve graft group. CONCLUSION: Bridging acellular nerve graft and bone marrow mesenchymal stem cells into rat sciatic nerve defects can promote motor functional recovery.