人脐血单个核细胞向神经细胞分化

Differentiation of mononuclear cells from human umbilical cord blood into neural cells

目的 :观察培养前后人脐血单个核细胞 (MNCs)的形态学及免疫反应性变化 ,探讨其能否向神经细胞的分化及机制。方法 :密度梯度离心脐血中单个核细胞 ,接种并用EGF和bFGF刺激细胞生长 ,倒置显微镜下观察培养前后细胞形态变化 ,并行免疫细胞化学鉴定。结果 :培养前脐血MNCs胞体小呈圆形 ,nestin阳性细胞、MAP2阳性细胞散在分布 (阳性率为 1 .5 %和 3 .4% )无GFAP阳性细胞着色。培养 1 4d后 ,细胞群中相邻细胞突起连成网状 ;MAP2、GFAP染色阳性细胞成片状分布 (阳性率 3 3 .5 %和 2 4.6% ) ,未见nestin阳性细胞。结论 :脐血细胞中可能有多能干细胞 。

Objective: To observe morphology and immunoreactivity changes of uncultured and cultured mononuclear cells(MNCs) derived from human umbilical cord blood,and to explore the feasibility of MNCs' differentiation into neural cells and its mechanism.Methods: MNCs were isolated by gradient centrifugation with Ficoll (the lymphocyte separation mediμm,1.077 g/cm 3). EGF and bFGF were used to accelerate cell growth.Phenotypic changes of uncultured and cultured MNCs were observed under inverse phase-contrast microscope. Cultured MNCs were identified by immunocytochemistry on 14th day.Results:Uncultrued MNCs were small and round.Nestin-positive cells (the positive rate was 1.5%) and MAP2-positive cells (the positive rate was 3.4%) were dispersely distributed. GFAP-positive cells were not observed in this experiment.Contiguous cultured MNCs wove into nets. MAP2-positive cells (the positive rate was 33.5%) and GFAP-positive cells (the positive rate was 24.6%) were made into sheets;nestin-positive cells were not observed.Conclusion:These results suggest that some multipotential stem cells may exist in umbilical cord blood and can differentiate into neural cells with special phenotypes in vitro.