神经干细胞在创伤性脑损伤灶周边的成活和迁移

Survival and migration of neural stem cells surrounding the lesion sites of traumatic brain injury

背景:成年人中枢神经系统再生困难,颅脑损伤后,损伤灶周边区域神经细胞的存活数量直接影响患者的预后。如何有效地使移植入创伤性脑损伤灶周边的神经干细胞存活分化,是目前神经修复再生研究的重点。目的:探讨神经干细胞移植入大鼠创伤性脑损伤灶周边的成活、迁移和分化情况。方法:利用无血清培养技术,加入表皮生长因子、碱性成纤维生长因子诱导刺激大鼠胚胎源性前脑神经干细胞生长增殖,并在体外进行克隆培养,移植前行BrdU标记,采用免疫组化和免疫荧光法检测其增殖特性和多向分化潜能,并观察其移植到Fenney’s落体脑损伤模型鼠脑皮质内的成活和迁移情况。结果与结论:免疫组化及免疫荧光检测结果显示克隆细胞球呈nestin和BrdU阳性,分化后呈NSE,GFAP,MAP-2阳性。免疫组化及荧光双标检测结果显示移植后7,14d损伤灶周边散在BrdU阳性细胞,并且GFAP阳性细胞增多。提示前脑神经干细胞在体外培养中能够增殖,并分化为神经元和神经胶质细胞,移植后能够在创伤性脑损伤灶周边存活和迁移,形态上显示出与脑组织整合的特点。

BACKGROUND：It is difficult to regenerate in the central nervous system of adults.Following traumatic brain injury, the number of surviving cells surrounding the lesion sites directly affects the patients＇ prognosis.How to make the transplanted neural stem and progenitor cells （NSPC） survival, migration and differentiation around the cortex damage in rats models of traumatic brain injury effectively are the keys of nerve regenerated and repair research.OBJECTIVE：To study survival, migration and differentiation of NSPC around the cortex damage in rats models of traumatic brain injury.METHODS：Using serum-free culture technique, epidermal growth factor and basic fibroblast growth factor were added to stimulate the origin of embryonic rat forebrain NSPC growth and proliferation.Moreover, in vitro clone culture was conducted.BrdU labeling, immunohistochemistry and immunofluorescence method were used to confirm the proliferation and multi-directional differentiation potential properties of NSPC.Survival and migration of transplanted NSPC were observed around the cortex damage in rat models of Fenney＇s traumatic brain injury.RESULTS AND CONCLUSION：Neural stem and progenitor cell clones were detected by immunohistochemistry and immunofluorescence method, which showed nestin-positive and BrdU-positive reaction.They displayed NSE-positive, GFAP-positive and MAP-2-positive reaction after NSPC differentiation in vitro.BrdU-positive cells were interspersed and GFAP-positive cells number was increased surrounding the cortex damage at 7 and 14 days posttransplantation.These suggested that rat forebrain neural stem and progenitor cells are able to proliferate and differentiate into neurons and glial cells, and can survive and migrate surrounding cortex damage, showing the characteristics of integrated into brain tissue in morphological observation.