粒细胞集落刺激因子对大鼠体内外源性人神经干细胞存活分化的影响

Effect of granulocyte-colony stimulating factor on survival of implanted human neural stem cells and the differentiation into oligodendrocytes

目的观察缺氧缺血脑损伤(hypoxic-ischemic brain damage,HIBD)新生大鼠应用粒细胞集落刺激因子(granulocyte-colony stimulating factor,G-CSF)对移植的人神经干细胞(human neural stem cells,hNSCs)体内存活及分化成少突胶质细胞的影响。方法新生1周的Wistar大鼠HIBD模型后分成两组:NSCs移植组(A组,n=24)和NSCs移植+G-CSF治疗组(B组,n=24),其中B组建模后1h即开始皮下注射G-CSF,每天1次,移植前后连续5d注射G-CSF。两组均于建模后第2天经脑室移植hNSCs。移植后3d用TUNEL法检测植入细胞凋亡情况,并于移植后1周、2周分别用免疫荧光法检测植入细胞在大鼠脑内的存活及向少突胶质细胞方向分化情况。结果移植后3d,A组大脑皮层见大量的植入细胞处于凋亡状态,而B组的植入细胞凋亡明显减少(t=68.36,P<0.01)。移植后1周及2周,可见植入细胞分布以额叶皮层和海马多见,纹状体亦有少许植入细胞分布,A组的植入细胞数少于B组(t=14.07和2.5,P<0.05)。而移植后1周及2周,hNSCs几乎不能分化成少突胶质细胞。结论 G-CSF能减少植入细胞的凋亡,提高植入细胞的存活率,但对植入细胞向少突胶质细胞方向的分化无影响。

Objective To examine the effect of granulocyte-colony stimulating factor （G-CSF） on survival of implanted human neural stem cells （hNSCs） and the differentiation into oligodendrocytes in neonatal rats with hypoxic-ischemic brain damage （HIBD）. Methods HIBD rats, born within a week, were divided into two groups randomly： the single transplan- tation group （Group A, n = 16） and the G-CSF ＋ transplantation group （Group B, n = 16）, in which G-CSF[- （ 50 μg/kg . d）-]was administered 1 hour after performing operation subcutaneously once a day for five days in a row. In both group ani- mals received implantation of hNSCs into the left cerebral ventricles at the second day after the operation. TUNEL staining was used to observe the apoptosis of the implanted cells in the rat brains 3 days post transplantation. While immunofluores- cence was used to detect the survival and oligodendroglial differentiation 1 week and 2 weeks after the transplantation. Re- sults Significantly decreased number of apoptosis cells was observed in group B compared to group A in 3 days after hNSCs transplantation （t= 68.36, P〈0.01）. The grafted cells detected by DAPI survived, and generally distributed among cortex, hippocampus, striatum,and other areas. The statistical analysis revealed that DAPI positive cells were more in rats of group B than those of group A （t= 14.07 and 2.5 respectively,P〈0. 05）. Differentiated oligodendrocytes of implanted cells could scarcely be seen in either group. Conclusion The survival of implanted cells is increased and apoptosis is reduced with G- CSF treatment,which has no effect on the differentiation of implanted hNSCs into oligodendrocytes.