College of Veterinary Medicine, Northwest AF University, Yangling, Shaanxi, 712100, Peoples Republic of China.
Cell Biol Int. 2011 Aug;35(8):849-56. doi: 10.1042/CBI20100899.
The aims of this study were (i) to determine whether NSCs (neural stem cells) could be isolated from the brain of embryonic day 98 fetal goat, (ii) to determine if these stem cells have the capability of multipotent differentiation following transfection with a reporter gene, EGFP (enhanced green fluorescent protein) and (iii) to study the characteristics of the stem cells cultured in attached and non-attached plates. NSCs were isolated from embryonic day 98 fetal goat brain, transfected with EGFP gene using lipofection, and subcultured in attached and non-attached plates respectively. The transgenic stem cells were induced to differentiate into osteogenic and endothelial cells in vitro respectively. Markers associated with undifferentiated NSCs and their differentiated cells were tested by RT-PCR (reverse transcription-PCR). The results demonstrated that stem cells could be isolated from embryonic day 98 fetal goat brain, and EGFP gene could be transfected into the cells. The transgenic NSCs were capable of self-renewal, a defining property of stem cells, and were grown as free-floating neurospheres in non-attached plates. When the neurospheres were transferred and cultured in attached plates, cells migrate from the neurospheres and are grown as spindle cells. The stem cells were grown as quasi-circular cells when the single stem cells were cultured in attached plates. Both the NSCs cultured in non-attached and attached plates could express Hes1 (hairy and enhancer of split 1), Oct4 (octamer-binding protein 4), Nanog, Sox2 [SRY (sex-determining region Y)-box 2] and Nestin, while following differentiation cells expressed markers for osteogenic cells (Osteocalcin+ and Osteonectin+) and endothelium (CD34+ and eNOS+). The results demonstrated that the goat EGFP gene transgenic NSCs have the capability of multipotent differentiation, which means that the transgenic NSCs may be useful in cell transplantation studies in future.
(i)确定是否可以从胚胎期 98 天的胎羊脑中分离神经干细胞(NSC);(ii)确定这些干细胞在转染报告基因 EGFP(增强型绿色荧光蛋白)后是否具有多能分化的能力;(iii)研究在附着和非附着平板上培养的干细胞的特性。从胚胎期 98 天的胎羊脑中分离 NSC,使用脂质体转染 EGFP 基因,并分别在附着和非附着平板上进行传代培养。将转基因干细胞在体外诱导分化为成骨细胞和内皮细胞。通过 RT-PCR(逆转录-PCR)检测与未分化 NSC 及其分化细胞相关的标记物。结果表明,能够从胚胎期 98 天的胎羊脑中分离出干细胞,并能将 EGFP 基因转染到细胞中。转染的 NSC 能够自我更新,这是干细胞的一个定义特征,并且在非附着平板上以自由漂浮的神经球形式生长。当神经球转移到附着平板上培养时,细胞从神经球中迁移出来,并以纺锤形细胞的形式生长。当单个干细胞在附着平板上培养时,干细胞生长为类圆形细胞。在非附着和附着平板上培养的 NSC 均能表达 Hes1(毛状和分裂增强因子 1)、Oct4(八聚体结合蛋白 4)、Nanog、Sox2[SRY(性别决定区 Y)-盒 2]和 Nestin,而分化后的细胞则表达成骨细胞(骨钙素+和骨粘连蛋白+)和内皮细胞(CD34+和 eNOS+)的标记物。结果表明,山羊 EGFP 基因转基因 NSC 具有多能分化的能力,这意味着转基因 NSC 可能在未来的细胞移植研究中有用。