星形胶质细胞源性因子对神经干细胞分化的实验研究

目的探讨星形胶质细胞源性因子对神经干细胞分化的影响。方法分离和培养新生大鼠脑组织的神经干细胞;采用差速贴壁法和振荡法分离纯化星形胶质细胞,用免疫细胞化学染色法,胶质纤维酸性蛋白(GFAP)标记星形胶质细胞,进行细胞的纯度鉴定;将星形胶质细胞和神经干细胞在互不接触的情况下进行共培养,免疫荧光法观察神经干细胞分化后神经元特异性烯醇化酶(NSE)、GFAP和酪氨酸羟化酶(TH)的表达。结果纯化的星形胶质细胞GFAP抗体标记阳性,细胞纯度达98%;星形胶质细胞与神经干细胞共培养时,神经干细胞贴壁分化加快,NSE阳性细胞及TH阳性细胞明显多于对照组(P<0·05)。结论星形胶质细胞源性因子可快速诱导神经干细胞向神经元细胞、包括多巴胺神经元细胞分化,提示星形胶质细胞支持神经元发生。

Experimental study on astrocyte-derived factors on the differentiation of neural stem cells

Objective To study the effect of astrocyte-derived factors on the differentiation of neural stem cells from neonatal rats. Methods Neural stem cells from neonatal rats were isolated, cultured and expanded by neurosphere formation. Astrocytes were isolated and purified by a standard shaking method and the differential adhesion technique. With immunocytochemical labeling, the purity of astrocytes was determined by the expression of glial fibrillary acidic protein(GFAP). Astrocytes and neural stem cells were co-cultured without contact. Immunofluorescence examination was used to detect the effects of astrocyte-derived factors on the expression of neuron specific enolase (NSE), GFAP, and tyrosine hydroxylase(TH) of the differentiated cells. Results The purified astrocytes were 98% of GFAP positive. Co-culturing the neurospheres with astrocytes promoted more neural stem cells rapidly differentiationinto NSE positive cells( P< 0.05 vs control) including more TH-positive cells induced( P< 0.05 vs control). Conclusions Astrocyte derived factors induced the differentiation of neural stem cells into neurons, including dopaminergic neurons. We conclude that mature astrocytes from neonatal rat brain promote neurogenesis.