体外培养的人脐血单个核细胞MAP2及τ蛋白mRNA的表达

Expression of microtubule-assosiated protein 2 and tau protein mRNA in mononuclear cells derived from human umbilical cord blood

目的:探讨脐血单个核细胞(MNCs)体外培养前后微管相关蛋白2(MAP2)和τ蛋白mRNA的表达。方法:用密度梯度离心法分离脐血MNCs,分组培养。对照组不加任何细胞因子,细胞因子组加入EGF和bFGF,终浓度均为20μg/L,每3d半量换液1次,共14d。倒置显微镜下观察培养过程中细胞形态的变化,RT-PCR法检测脐血MNCs培养前后τ蛋白及MAP2mRNA的表达。结果:培养前,脐血MNCs胞体小呈圆形。培养后细胞因子组细胞胞体较大,有粗长突起形成,类似神经元;对照组细胞胞体较小,突起较短、较细,形似星形细胞。培养前脐血MNCsτ蛋白mRNA阴性表达,而MAP2mRNA表达阳性;培养后2者均表达阳性,且细胞因子组2者阳性表达强于对照组(P<0.05)。结论:脐血MNCs表达MAP2mRNA,经培养后同时表达τ蛋白mRNA,细胞因子能增强2者的表达。

Aim ： To observe the expression of microtubule-assosiated protein 2 （MAP2） and tau protein mRNA of cultured and un-cultured mononuclear cells（MNCs） derived from human umbilical cord blood. Methods： The isolated MNCs from umbilical cord blood samples by centrifugation, were cultured with （cytokine group） or without （control group） EGF ＋ bFGF at a final concentration of 20μg/L. Morphological changes of MNCs were monitored by inverse phase-contrast microscopy. MAP2 and tau mRNA were determined by RT-PCR before and after 14 d culture. Results： The freshly isolated MNCs were small and round. After culture, some cells of cytokine group became larger and were like neuron,and there were. some small cells like astrocyte in the control group. The expression of tau protein mRNA was negative, but MAP2 mRNA was positive in uncultured cells;after cuhure, the expression of MAP2 and tau protein mRNA were both positive, and those of cytokine group were higher than those of control group. Conclusion ： Human MNCs could express MAP2 mRNA before and after incubation, express tau mRNA only by incubation, and the combination of EGF and bFGF can upregulate tau and MAP2 mRNA expression in cultured MNCs.