神经生长因子基因转染间充质干细胞移植对损伤脊髓保护的实验研究

目的 探讨神经生长因子(NGF)基因转染间充质干细胞(MSCs)移植对损伤脊髓的保护作用.方法 近交系Wistar大鼠(n=56),随机分为治疗组、空白组、对照组,采用改良的Allen打击法造成脊髓损伤(SCI)的模型;分离培养同种异体MSCs,纯化、扩增后,MSCs经绿色荧光蛋白(GFP)标记并被NGF基因转染后重新悬垂(1×108/ml)于SCI 7 d后移植入受损硬脊膜下.对照组注射等量的磷酸盐缓冲液(PBS),分别在MSCs移植后24 h和1、2周后取损伤脊髓段冰冻切片,.在荧光显微镜下观测移植细胞的分布情况;观测MSCs移植后胶质纤维酸性蛋白(GFAP)和NGF表达的变化;进行神经功能(BBB)评价. 结果 MSCs移植后可向损伤脊髓中心聚集,SCI后.治疗组GFAP和NGF的表达明显高于对照组(P<0.05);BBB评分显示治疗组和对照组神经功能差异有统计学意义. 结论 NGF基因转染的MSCs移植促进了脊髓神经功能的恢复,移植后具有一定的分布规律.

Experimental study of repairing acute spinal cord injury with transplantation of mesenchymal stem cells genetically modified by NGF in rats

Objective To investigate mesenchymal stem cells genetically modified by nerve growth factor to repair acute spinal cord injury in rats. Methods Fifty six Wistar rats of inbred strain were randomly divided into sham operation group cell transplantation group and simple injury group. The spinal cord injury model was prepared according to the modified Allen's method. NGFβ (hNGFβ) and GFP genes were transfected into MSCs by replication-deficient recombinant adenovirus vector (Ad-hNGFβ) and replication-deficient recombinant retrovirus vector (Rt-GFP) respectively. GFP positive MSCs were transplanted into intradural space of injured spinal cord at 7 days after spina coral injury. Spinal cord was dissected at 24 h, 1 and 2 weeks after transplantation. To observe the expression of GFAP and nestin and the distribution of MSCs after transplantation following the spina corol injury. Results MSCs migrated to the injured parenchyma In transplantation group, the expression of GFAP and NGF protein was higher than in the control group (P<0.05), the BBB score in transplantation group was higher than that in the control group (P<0.05). Conclusion The MSCs transplantation repaired the injured spinal cord to some extent.