中文摘要：

目的利用腺病毒载体转染体外培养的肝前体细胞，研究过表达Wnt3对肝前体细胞凋亡的影响。方法用携带Wnt3的腺病毒载体（Ad-wnt3）转染肝前体细胞，同时设立空载体腺病毒转染组（Ad-GFP）为对照。转染72h后，用荧光显微镜观察Hoechst33342染色后细胞凋亡情况；流式细胞术检测Annexin-PE／7-ADD法标记的细胞凋亡率；RT-PCR和Western blot分别检测细胞凋亡相关蛋白Bax、Bcl-2和Bcl-xl的mRNA及蛋白表达水平。结果qRT-PCR和Westernblot结果显示，Wnt3在肝前体细胞中特异性表达，表明腺病毒系统Ad-Wnt3能高效转染肝前体细胞。与对照组相比较，肝前体细胞转染Wnt3后，肝前体细胞的凋亡水平明显下降，凋亡相关蛋白Bcl-2和Bcl-xl的mRNA及蛋白表达水平明显升高（P〈0．05）。Bax的mRNA及蛋白表达水平则明显下降（P〈0．05）。结论在肝前体细胞中，Wnt3基因过表达能抑制肝前体细胞凋亡，其机制可能是通过Bcl-2家族起作用。

英文摘要：

Objective To investigate the effects of adenoviral vector-mediated over-expression of Wnt3 on the apoptosis of hepatic progenitor cells in vitro. Methods Hepatic progenitor ceils transfected with Ad-GFP-Wnt3 vector or the control vector Ad-GFP were examined for cell apoptosis under fluorescence microscopy with Hoechst 33342 staining, and the proportion of apoptotic cells were determined by flow cytometric analysis with Annexin-PE/7-ADD staining. The mRNA and protein expressions of Bax, Bcl-2 and Bcl-xl in the cells were detected by real-time PCR and Western blotting, respectively. Results Real-time PCR and Western blotting showed a high expression of Wnt3 in Ad-GFP-Wnt3-transfected hepatic progenitor ceils, which exhibited significantly decreased cell apoptosis as compared with the control group. The expressions of Bcl-2 and Bcl-xl mRNA and proteins increased significantly while Bax expression decreased obviously in Ad-GFP-Wnt3-transfected cells （P〈 0.05）. Conclusion Adenoviral vector-mediated over-expression of Wnt3 can suppress apoptosis of hepatic progenitor cells possibly through the Bcl-2 pathway.