大鼠神经干细胞体外培养条件下GDNF及NGF的分泌特点

目的：探讨体外培养条件下大鼠神经干细胞（NSCs）分泌胶质细胞源性神经营养因子（GDNF）和神经生长因子（NGF）的特点。方法：取SD胎鼠NSCs悬浮培养，光镜观察细胞形态，使用Nestin、微管相关蛋白2（MAP-2）、胶质纤维酸性蛋白（GFAP）、半乳糖神经鞘氨醇酶（GalC）免疫荧光法鉴定细胞。培养第3代后使用ELISA法测量其GDNF及NGF分泌量，连续测量6代。结果：光镜下第3代细胞仍保持较多NSCs特征，至第6代，大部分干细胞分化为星形胶质细胞，少部分分化为神经元或少突胶质细胞。第3代细胞GDNF的分泌量较低，但随着培养时间的延长，其分泌量逐渐增高；而第3代细胞NGF的分泌量较高，但其分泌有一个高峰期（第6代），随后逐渐下降。结论：在体外培养条件下，NSCs干细胞阶段分泌GDNF的能力较低，而分泌NGF的能力较高；进入分化阶段后，分泌GDNF的能力提高，而分泌NGF的能力有所减弱。利用干细胞移植治疗中枢神经系统损伤时应注意时程的选择。

GDNF and NGF Secretions of Cultured Neural Stem Cells

Objective:To investigate the status of GDNF and NGF secretions of cultured neural stem cells in vitro.Methods:Neural stem cells(NSCs) of S-D rats were prepared and identified by immunocytochemistry.The secretions of GDNF and NT-3 were measured by ELISA.Results:Majority of the cells in the third passage were determined as neural stem cells.In the sixth passage,most stem cells differentiated into astrocytes as indicated by the expression of GFAP while few expressed specific markers for neurons or oligodentroc...