碱性成纤维生长因子和表皮生长因子对脊髓神经干细胞增殖与分化的影响

Effect of Fibroblast Growth Factor and Epidermal Growth Factor on the Proliferation and Differentiation of Neural Stem Cells From Embryonic Spinal Cord

目的观察碱性成纤维生长因子(bFGF)和表皮生长因子(EGF)对胚胎脊髓神经干细胞(NSC)增殖与分化的影响。方法从14 d胚胎大鼠的脊髓组织中分离培养脊髓NSC,并随机分为3组:EGF组、bFGF组和bFGF+EGF组。通过光镜观察不同时间点各组脊髓NSC克隆细胞团数量及直径大小,并采用免疫荧光染色检测各组脊髓NSC向神经元和星形胶质细胞分化的情况。结果①EGF组培养1、3、7 d后NSC克隆细胞团数量和直径均少于bFGF和bFGF+EGF组,差异有统计学意义(P<0.05)。而bFGF+EGF组仅在培养1 d时克隆细胞团数量多于bFGF组,在培养3、7 d时差异无统计学意义。②EGF组分化细胞中神经元比例显著少于bFGF和bFGF+EGF组,星形胶质细胞数量明显大于bFGF和bFGF+EGF组,差异有统计学意义(P<0.05)。而bFGF和bFGF+EGF组组间差异无统计学意义。结论 EGF对脊髓NSC克隆形成有一定作用,而bFGF能较好地促进克隆细胞团的形成及生长,两者联合应用在培养早期可显著促进克隆细胞团形成。EGF可诱导脊髓NSC更多分化为星形胶质细胞,而bFGF则可促进脊髓NSC向神经元分化。

Aim To observe the effect of basic fibroblast growth factor （bFGF） and epidermal growth factor （EGF） on the proliferation and differentiation of neural stem cells （NSC） from embryonic spinal cord. Methods NSC were isolated from embryonic 14 d spinal cord tissue of rats and randomly divided into three groups： EGF, bFGF and bFGF＋EGF groups. The number and diameter of clones were observed under microscrope. At the same time the differentiation of NSC towards neuron and astrocyte were examined with immunofluorescent staining. Results The number and diameter of neural stem cell clones in EGF group were less than that ofbFGF and bFGF＋EGF groups after 1, 3, 7 days in culture. The number of clones in bFGF＋EGF group was more than that ofbFGF group only after 1 day culture, but there was no difference after 3, 7 days between the two groups. The ratio of differentiated neurons in EGF group were significantly less than that in bFGF and bFGF＋EGF groups, in contrast, the number of astrocytes were more than that in bFGF and bFGF＋EGF groups. However, there was no difference between bFGF and bFGF＋EGF groups. Conclusion EGF has limited effect on the formation of neural stem cell clones from spinal cord, but bFGF can promote the formation and growth of neural stem cells clone. The combination of EGF and bFGF can significantly increase the number of clone in prophase. EGF can induce neural stem cells differentiate into more astrocytes, but bFGF can promote neural stem cells to differentiate into more neurons.