决定肝细胞对乙型肝炎病毒易感性的关键分子研究

乙肝病毒(HBV)高度嗜肝，人体细胞中仅肝实质细胞对HBV易感。受体NTCP的发现是肝细胞HBV易感机制研究中重要进展。HepG2等非易感细胞，在稳定转染NTCP后可支持HBV感染。但与体内感染相比较，HepG2/NTCP模型在感染效率等方面仍有显著差距，迄今亦无报道显示人NTCP转基因鼠对HBV易感。因此，存在NTCP以外的肝细胞特异性分子，影响乃至决定着肝细胞对HBV的易感性。申请人在此前工作中发现新鲜分离的树鼩原代肝细胞对HBV感染易感性随培养时间延长而显著下降，提示易感性相关基因表达水平发生明显变化。本项目拟从上述现象出发，通过对树鼩原代肝细胞培养过程中基因表达变化的组学分析，结合基于生物信息学和HBV感染细胞模型的功能研究，筛选、鉴定未知的决定肝细胞HBV易感性的关键基因，研究其在HBV感染中所起作用，深入揭示HBV感染的分子机制，并为针对HBV感染过程的基础和应用研究提供工具。

Hepatitis B virus (HBV) is highly hepato-tropic and hepatocytes are the only cell types susceptible to HBV infection. The identification of NTCP as receptor for HBV represents a significant advance in understanding mechanisms of hepatocytes’ susceptibility to HBV infection. Insusceptible cell lines like HepG2 that do not support HBV infection can be rendered susceptible to HBV infection by stable transfection of NTCP. However, compared to HBV infection in vivo, HepG2/NTCP infection system is far inferior in the respects of infection efficiencies, etc. Additionally, there is no evidence showing that mice transgenic for human NTCP can support HBV infection. Therefore, it is highly likely that these exist molecules other than NTCP that affect, and maybe even determine, hepatocytes’ susceptibility to HBV infection. In our previous work, we observed that susceptibility of primary tupaia hepatocytes (PTH) to HBV infection declined significantly during continuous culture, suggesting that expression level of susceptibility-determining genes changed considerably in this process. Based on this observation, this study intends to characterize changes in gene expression profiles during prolonged culture of PTH using transcriptomic and proteomic approaches, and by combining bioinformatic analyses and analyses using HBV infection systems, screen and identify genes critical for hepatocytes’ susceptibility to HBV. This study will then probe functions played by these genes in HBV infection, which will reveal further details of the molecular mechanisms of HBV infection and also generate tool systems for basic and applied research targeting HBV infection.