壳聚糖复合导管与人脐带间充质干细胞对神经侧芽分化生长的作用

Chitosan conduits with human umbilical cord mesenchymal stem cells induce differentiation and growth of the nerve lateral bud

背景:人脐带间充质干细胞与骨髓间充质干细胞相类似,在特定环境下可以定向分化成神经样细胞,可以按需分泌各种因子,提供神经再生的基质和基础细胞。目的:研究桥接人脐带间充质干细胞壳聚糖复合神经导管在神经端侧吻合中的作用。方法:将30只大耳白兔随机均分为3组,切断右后侧腓总神经中部分支,近端结扎,翻转缝合于肌肉内,对照组将腓总神经远断端与胫神经以30°-45°夹角行传统端侧吻合,支架组以同等间隙及夹角桥接壳聚糖导管于胫神经-腓总神经端侧吻合口间,细胞-支架组以同等间隙及夹角桥接填充人脐带间充质干细胞的壳聚糖复合导管于胫神经-腓总神经端侧吻合口间。术后12周行大体观察、神经电生理和抗S-100免疫组织化学检测。结果与结论:术后12周,细胞-支架组壳聚糖复合神经导管完全降解,神经直径接近正常腓神经,运动神经传导速度快于对照组与支架组(P<0.01);抗S-100免疫组织化学显示,细胞-支架组可见大量棕红色增殖的许旺细胞排列在再生神经纤维周围,支架组与对照组棕红色物质少而稀疏,许旺细胞生长情况较差。表明人脐带间充质干细胞在神经端侧吻合中对神经再生有明显促进作用,对诱导轴芽生长,加快再生纤维生长速度,促进许旺细胞生长及成熟有显著意义。

BACKGROUND：Human umbilical cord mesenchymal stem cells are similar to bone marrow mesenchymal stem cells, which can directional y differentiate into neuron-like cells, secrete various cytokines, and provide the base for nerve regeneration. OBJECTIVE：To study the role of chitosan composite nerve conduit carrying umbilical cord mesenchymal stem cells in nerve end-to-side anastomosis. METHODS：Thirty while rabbits were randomized into three groups. The central branch of the right posterior peroneal nerve were cut and proximal y ligated, and then sutured evaginably to the muscle. In the control group, the distal end of the common peroneal nerve were anastomosed into the tibial nerve at 30°-45°;in the stenting group, the chitosan conduit was bridged at the same interval and angle into the end-to-side anastomosis site between the tibial nerve and peroneal nerve;in the cel-stenting group, the chitosan conduit carrying human umbilical cord mesenchymal stem cells was bridged at the same interval and angle into the end-to-side anastomosis site between the tibial nerve and peroneal nerve. After 12 weeks, gross observation, neurophysiological examination and anti-S-100 immunohistochemistry detection were performed. RESULTS AND CONCLUSION：After 12 weeks of operation, in the cel-stenting group, the conduit degraded completely, the nerve diameter was similar to that of the normal peroneal nerve, and the motor nerve conduction＆amp;nbsp;velocity was higher than that in the control and stenting groups （P〈0.01）. Anti-S-100 immunohistochemistry results showed that a great amount of brownish red Schwann cells arranged around the regenerated nerve fibers in the cel-stenting group, while there was few and sparse brownish red substance, and the Schwann cells grew worse in the stenting and control groups. These findings suggest that umbilical cord mesenchymal stem cells have an obvious role in promoting nerve regeneration, induce bud growth, accelerate the growth rate of regenerated fibers, and improve growth and maturity of Schwann cells.