中文摘要：

目的：研究人类疱疹病毒6型（HHV-6）感染人星形胶质瘤细胞U251,及感染后对其生物学功能的影响。方法：HHV-6感染U251细胞建立HHV-6体外感染模型,倒置显微镜观察细胞病变。PCR法检测HHV-6u22基因。间接免疫荧光（IFA）检测HHV-6即刻早期蛋白（IE1）和晚期蛋白（gB）的表达。MTT法检测U251感染HHV-6后细胞增殖的改变。流式细胞术（FCM）检测U251细胞周期改变。结果：在感染3天后U251出现典型细胞病变,细胞肿胀增大数倍,透亮,呈多形性。PCR检测到HHV-6u22基因。IFA检测到HHV-6IE1蛋白和gB蛋白的表达。MTT法显示HHV-6能增强U251细胞的增殖能力。FCM检测表明,HHV-6感染后U251细胞周期发生改变,感染组和对照组相比,前者G1期的细胞减少,S期和G2期细胞增多。结论：HHV-6能感染U251细胞引起细胞病变,促进细胞的增殖,使细胞周期发生改变。本研究结果提示人类疱疹病毒6型可能参与人神经胶质瘤的发生、发展,对其机制尚不清楚。

英文摘要：

Objective：To study the significance of human herpesvirus type 6 （HHV-6） infection on U251 astroglioma cells and its effects on biological functions of the cells. Methods：The model of HHV-6 infection in vitro was developed by infection of U251 cells with HHV-6. Synchronized U251 were infected with HHV-6. Cytopathic effect（CPE）were visualized by inverted phase contrast microscope. u22 gene of HHV-6 was amplified by PCR. The expression of immediate early protein 1 （IE1） and late protein（gB） were determined by indirect immunofluorescence assay （IFA）. The proliferation of U251 cells was determined by MTT method,and the cell cycle was detected by flow cytometry analysis（FCM）. Results：After 3 days,cells infected with the HHV-6 showed the typical cytopathic effect, cell swelling and the appearance of translucence and pleomorphism. u22 gene of HHV-6 was detected by PCR. HHV-6 immediate early protein 1 （IE1） and late protein （gB） were positive in the cultured cells by indirect immunofluorescence assay （IFA）. HHV-6 could promote U251 cells proliferation by MTT assay. The FCM assay showed that the cycle of the infected U251 cells changed, compared infected groups with control groups,the former G1 phase cells decreased,and cells in S phase and G2-phase increased significantly. HHV-6 could promote U251 cells proliferation. Conclusion：HHV-6 can infect the U251 cells,cause cytopathic,stimulate cell proliferation,and change cell cycle. The results of this study indicated that HHV-6 might be correlated with the genesis and development of gliocytoma,but its mechanism is not clear.