人神经干细胞移植修复大鼠脊髓损伤的实验研究

Treatment of rats with spinal cord injury with transplanting human neural stem cells

目的研究人神经干细胞（hNSCs）移植对大鼠脊髓损伤的修复作用，并初步探讨其作用原理。方法分离、培养和鉴定hNSCs。24例成年SD大鼠分为移植组12例和对照组12例，均采用NYU-Ⅱ型脊髓打击器制作脊髓损伤模型，第9天移植组于损伤脊髓中心分别注入经CM-DiI标记的hNSCs混悬液，对照组注入人DMEM／F12培养液。术后第4、8周取损伤部位脊髓，免疫组织化学染色检测移植细胞的存活和分化；术后每7天行BBB评分，评定大鼠后肢运动功能恢复情况。数据进行成组设计资料的t检验。结果成功建立hNSCs的体外培养体系；移植的hNSCs在大鼠脊髓内存活超过8周，并向脊髓损伤头尾端迁移，免疫组织化学荧光染色示移植细胞可分化为神经元、少突胶质细胞和星形胶质细胞；移植组大鼠BBB评分高于对照组（P〈0．05）。结论移植到大鼠损伤脊髓中的人神经干细胞可分化为神经元和神经胶质细胞，并可促进脊髓损伤大鼠后肢运动功能恢复。

Objective To study the effects of human neural stem cells （hNSCs） transplantation on rats with spinal cord injury （SCI）. Methods After hNSCs were isolated and identified, Twenty-four adult SD rats were removed of T10 vertebral plate and Twenty-four had spinal cord injury by NYU- Ⅱ system. Twenty-four SCI rats were randomly divided into experimental group （n = 12） and control group （n = 12）. hNSCs marked with CM-DiI were transplanted into the spinal cord of experimental group on the 9th day. Immunohistochemistry staining was applied to detect the survival and differentiation of the transplanted cells in vivo, and BBB loco motor rating scale was used to assess the recovery of the hind-limb function. Results hNSCs culture system in vitro was established successfully. The transplanted hNSCs could survive for at least 8 weeks, and migrate as far as 10mm away from the lesion edge, expressing differentiation markers for neurons, oligodendrocytes and astrocytes in vivo, Compared with the control group, the hind-limb function in experimental group was significantly improved. Conclusion hNSCs which were transplanted into the injured adult rat spinal cord could differentiate into neurons and neural glail cells, and improve the hind-limb function recover.