人胚胎神经干细胞的分离培养及鉴定

目的探索人胚胎神经干细胞的体外分离培养条件,并观察神经干细胞增殖、分化的特点.方法采用机械方法从流产的10～18周胎龄的人胚胎前脑分离神经干细胞,用无血清培养液,加入表皮生长因子(EGF)和碱性成纤维细胞生长因子(bFGF)刺激细胞增殖,进行体外扩增、传代培养.传3～4代的神经细胞球在含10%胎牛血清的DMEM/F12培养液贴壁诱导分化培养.采用免疫荧光法鉴定神经干细胞和分化的神经元、星形胶质细胞及少突胶质细胞.结果从人胚胎前脑分离的细胞在含有EGF和bFGF的无血清培养液中能形成大量的神经细胞球,这些神经细胞球可在体外增殖及传代培养.神经细胞球用特异性的鼠抗人巢蛋白(nestin)抗体鉴定,大部分为阳性细胞.神经细胞球在血清培养液贴壁培养后可分化出神经纤维细丝(NF)、胶质纤维酸性蛋白(GFAP)、半乳糖脑苷脂(Gal-C)表达阳性的细胞.结论从人胚胎前脑分离的细胞具有自我更新能力和多向分化潜能,属于神经干细胞;在含有EGF和bFGF的无血清培养液中,神经干细胞能在体外大量扩增.

Culture and identification of neural stem cells from the forebrain of human embryo

Objective To investigate the methods of cultivation and expansion of neural stem cells in vitro. Methods Neural stem cells were isolated from forebrain of human embryo and cultured in the serumfree medium containing EGF and bFGF. Immunocytofluorescence was used to identify the neural stem cells and the differentiated cells. Results The cells from forebrain of human embryo were able to proliferate in the serum-free medium containing EGF and bFGF. By immunocytofluorescence, the neurospheres were found to be nestin positive and they differentiated into NF positive cells, GFAP positive cells and Gal-C positive cells in cultures with fetal bovine serum. Conclusion The isolated cells from forebrain of human embryo have the ability of self-renewal and multipotent differentiation.