不同TGF-β表达量的hAMSCs尾静脉移植对异种周围神经移植小鼠坐骨神经功能的影响

目的探讨不同转化生长因子-β(TGF-β)表达量的人羊膜间充质干细胞(hAMSCs)尾静脉移植对异种周围神经移植小鼠坐骨神经功能的恢复作用。方法从健康剖宫产产妇志愿捐献的新鲜羊膜中分离出hAMSCs,并进行纯化及鉴定。构建上调和下调TGF-β表达的慢病毒质粒,并转染纯化的hAMSCs,构建出稳定的上调或下调TGF-β表达的hAMSCs。分离并剪去C57BL/6小鼠的部分坐骨神经,将SD大鼠的坐骨神经分离剪取并移植至小鼠的坐骨神经缺损处,构建出异种周围神经移植小鼠模型。将模型小鼠按随机数字表分为对照组、未修饰的hAMSCs治疗组、高表达TGF-β的hAMSCs治疗组、低表达TGF-β的hAMSCs治疗组,每组10只。各组于造模前1 d分别经尾静脉注射磷酸盐缓冲液或相应的hAMSCs重悬液进行移植治疗。于治疗后第14天时采用DigGait步态分析系统评估各组小鼠的坐骨神经功能恢复情况。结果治疗后第14天时,高表达TGF-β的hAMSCs治疗组小鼠的坐骨神经功能指数(-25.820±0.286)明显高于低表达TGF-β的hAMSCs治疗组(-33.413±0.920)和未修饰的hAMSCs治疗组(-30.755±0.421),差异均有统计学意义(P<0.05)。结论高表达TGF-β的hAMSCs尾静脉移植能够更有效地改善异种周围神经移植小鼠的坐骨神经功能,其可能成为周围神经损伤治疗的新突破口。

Effect of tail vein transplantation of human amniotic mesenchymal stem cells with different transforming growth factor-βexpressions on sciatic nerve function in xenografted mice

Objective To investigate the effect of tail vein transplantation of human amniotic mesenchymal stem cells(hAMSCs)with different transforming growth factor(TGF)-βexpressions on recovery of sciatic nerve function in peripheral nerve xenotransplantation mice.Methods The hAMSCs were isolated from amnion membranes by healthy mother donors and identified by fluorescence activated cell sorter.The up-regulated and down-regulated TGF-βlentiviral plasmids were constructed and transfected into the purified hAMSCs;hAMSCs with stable up-regulated or down-regulated TGF-βexpression were constructed.The sciatic nerves of C57BL/6 mice were isolated and cut out,and sciatic nerves of SD rats were isolated and transplanted into the sciatic nerve defected C57BL/6 mice to construct peripheral nerve xeno-transplanted mice models;these mice models were divided into 4 groups(n=10)according to random number table:control group,hAMSCs treatment group,high-expressed TGF-βhAMSCs treatment group,and low-expressed TGF-βhAMSCs treatment group;one d before modeling,phosphate buffer saline(PBS)or hAMSCs re-suspension were drawn with a syringe and slowly pushed into the tail veins of mice for transplantation treatment;14 d after treatment,DigGait analysis system was used to evaluate the recovery of sciatic nerve function in each group of mice.Result Fourteen d after treatment,the sciatic nerve function index(SFI)of the high-expressed TGF-βhAMSCs treatment group(-25.820±0.286)was significantly higher than that of the low-expressed TGF-βhAMSCs treatment group(-33.413±0.920)and hAMSCs treatment group(-30.755±0.421,P<0.05).Conclusion The tail vein transplantation of hAMSCs with TGF-βhigh expression can effectively improve the sciatic nerve function in peripheral nerve xenotransplantation mice,which may be a new breakthrough in the treatment of peripheral nerve defects.