Human apolipoprotein E is required for infectivity and production of hepatitis C virus in cell culture
Human apolipoprotein E is required for infectivity and production of hepatitis C virus in cell culture
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DOI：
10.1128/jvi.01091-07
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发表时间：
2007-12-01
影响因子：
5.4
通讯作者：
Luo, Guangxiang
中科院分区：
文献类型：
--
作者：
Chang, Kyung-Soo;Jiang, Jieyun;Luo, Guangxiang
丙型肝炎病毒（HCV）反向遗传学研究的最新进展，使得确定HCV病毒粒子的性质和生化组成成为可能。在培养的细胞中产生的含HCV RNA的颗粒的沉降分析和表征显示，HCV病毒体在蔗糖梯度中覆盖大范围的异质密度。低密度的组分具有感染性，而含有大部分HCV病毒体RNA的高密度组分则没有感染性。感染性HCV病毒颗粒中检测到HCV核心蛋白、载脂蛋白B和载脂蛋白E（apoE）。apoE水平与HCV感染性密切相关。载脂蛋白E和HCV E2特异性单克隆抗体沉淀HCV，表明HCV病毒体含有载脂蛋白E和E2蛋白。apoE特异性单克隆抗体以剂量依赖性方式有效中和HCV感染性，导致感染性HCV减少近4个数量级。通过特异性小干扰RNA（siRNA）敲低apoE表达显著降低了细胞内以及分泌的HCV病毒体的水平。apoE siRNA在50 nM时抑制HCV产生超过100倍。这些发现表明，载脂蛋白E是所需的HCV病毒粒子的感染性和生产，这表明HCV病毒粒子组装为载脂蛋白E富集的脂蛋白颗粒。我们的研究结果还确定了载脂蛋白E作为一个新的目标，发现和开发的抗病毒药物和单克隆抗体，以抑制HCV病毒粒子的形成和感染。
Recent advances in reverse genetics of hepatitis C virus (HCV) made it possible to determine the properties and biochemical compositions of HCV virions. Sedimentation analysis and characterization of HCV RNA-containing particles produced in the cultured cells revealed that HCV virions cover a large range of heterogeneous densities in sucrose gradient. The fractions of low densities are infectious, while the higher-density fractions containing the majority of HCV virion RNA are not. HCV core protein and apolipoprotein B and apolipoprotein E (apoE) were detected in the infectious HCV virions. The level of apoE correlates very well with HCV infectivity. Both apoE- and HCV E2-specific monoclonal antibodies precipitated HCV, demonstrating that HCV virions contain apoE and E2 proteins. apoE-specific monoclonal antibodies efficiently neutralized HCV infectivity in a dose-dependent manner, resulting in a reduction of infectious HCV by nearly 4 orders of magnitude. The knockdown of apoE expression by specific small interfering RNAs (siRNAs) remarkably reduced the levels of intracellular as well as secreted HCV virions. The apoE siRNA suppressed HCV production by more than 100-fold at 50 nM. These findings demonstrate that apoE is required for HCV virion infectivity and production, suggesting that HCV virions are assembled as apoE-enriched lipoprotein particles. Our findings also identified apoE as a novel target for discovery and development of antiviral drugs and monoclonal antibodies to suppress HCV virion formation and infection.