中文摘要：

目的：探讨体外培养的人肝细胞系在重组人转化生长因子β1（TGF-β1）诱导下是否发生上皮-间质转化（epithelial-mesenchyme transition,EMT）以及相关标志物的表达变化。方法：人类肝细胞HL7702在含20%小牛血清的1640培养液培养2 d,改用无血清培养并TGF-β1分别诱导24 h,48 h,72 h;观察诱导前后细胞的形态学变化,实时荧光定量RT-PCR及蛋白质免疫印迹技术分析细胞中EMT相关基因和蛋白表达情况。结果：显微镜下观察到TGF-β1诱导前,肝细胞是不规则的六边形,诱导后细胞形态拉长变成纺锤形,细胞间隙变大;实时荧光定量RT-PCR和免疫印迹显示上皮化标志物E-钙黏附蛋白在TGF-β1诱导后的细胞中表达显著下降,而间质化标志物N-钙黏附蛋白、波形蛋白和Twist却显著增加。结论：正常人类肝细胞株HL7702经重组人TGF-β1的诱导发生上皮-间质转化,这为深入研究TGF-β1和肝纤维化之间的关系奠定了基础。

英文摘要：

Objective： To investigate whether hepatocytes could undergo epithelial-mesenchyme transi- tion （EMT） on recombinant TGF-β1 stimulation in vitro. Methods： Human hepatocyte line HL7702 were cultured for 2 days with 20% NBS（1640） nutrient medium, and changed for serum-free 1640 medium and TGF-β1 factor induced HL7702 cells for 24,48,72 h. Cells morphology changes were watched before and after induction with inverted microscope. Real-time RT-PCR and western blot were used to analyze the ex- pression of epithelial and mesenchyme cells-associated genes and proteins. Results： Hepatocytes before TGF-β1 induction were irregular sixangle cells. After stimulation cells showed spread and spindle-shaped morphology and cell-cell junction got bigger. Real-time RT-PCR and western blot analysis showed that epi- thelial marker-associated E-cadherin expression decreased obviously after TGF-β1 induction, while mesen- ehyme markers N-cadherin, Vimentin, Twist increased significantly. Conclusion： Human hepatocyte line HL7702 happened to EMT by recombinant TGF-β1 stimulation. EMT associated epithelial and mesenchyme genes and proteins expression changed significantly. It could be served as a foundation for further investiga- tion ota the mechanism of hepatocytes EMT.