Ferumoxides标记神经干细胞及其对增殖分化的影响

Experimental study on biological characteristics of ferumoxides labeled neural stem cells

目的:研究超顺磁性氧化铁(superparamagneticironoxides.SPIOs)标记神经干细胞及其生物学特性。方法:神经干细胞培养、传代和诱导分化;菲立磁(Ferumoxides,一种SPIOs)标记神经干细胞,制备磁标记神经干细胞;利用免疫细胞化学、透射电镜和Prussianblue染色等方法对磁标记神经干细胞的生长、分化等生物学特性进行研究。结果:在原代及传代细胞中有Nestin阳性细胞即神经干细胞。血清诱导下,神经干细胞可分化为GFAP、MAP - 2、NSE、Tau蛋白及NF2 0 0阳性细胞。Feru moxides与神经干细胞共同孵育后,透射电镜及Prussianblue染色显示胞浆中含有铁颗粒,SPIOs也可以随细胞的分裂增殖而传到子代细胞中。随Ferumoxides浓度的增高(2 .8μg/ml～16 .8μg/ml) ,Ferumoxides对神经干细胞存活、分化能力的影响无显著性差异(P >0 .0 5 )。当Ferumoxides的浓度大于2 2 .4 μg/ml时,SPIOs影响其存活和分化(P <0 .0 5 )。结论:本实验在国内首次利用Ferumoxides作为磁标记探针,对神经干细胞进行成功磁标记。为进一步利用核磁共振(MRI)对神经干细胞活体追踪奠定实验基础。

Objective:To study the biological characteristics of superparamgnetic iron oxides(SPIOs)labeled neural stem cells(NSCs).Methods:The culture,passage and differentiation of NSCs were completed from newborn rat brain.Ferumoxides labeled NSCs were prepared as magnetic labeled NSCs.Using immunocytochemistry,transmission electron microscopy(TEM) and Prussian blue staining,the growth,differentiation and other biological characteristics were studied.Results:Nestin positive cells were found in the culture and daughter clones.NSCs could be differentiated into positive GFAP,MAP-2,NSE,Tau protein and NF200 cells in serum culture.When NSCs incubated with ferumoxides,the iron particles were seen in intracellular(non-nucleus)as well as in dauhgter clones.With the increase in concentration of ferumoxides(2.8μg/ml～16.8μg/ml),it showed no significant difference in effects on the growth and differentiation of NSCs(P>0.05).When the concentration of ferumoxides exceeded 22.4μg/ml,there was significant difference(P<0.05).Conclusion:In China,ferumoxides is first successfully used to label NSCs,a kind of SPIOs with magnetic labeled NSCs,which provides experimental basis for tracing magnetic labeled NSCs in vivo with MRI.