目前, 对丙型肝炎病毒( HCV) 感染的患者主要采用以Ⅰ型干扰素为主的治疗方案, 但干扰素抑制病毒的具体机制仍然不详。本研究通过实时聚合酶链反应( PCR) 检测HCV的RNA 水平, 蛋白免疫印迹法检测HCV 非结构蛋白的表达, 以及膜飘浮实验检测非结构蛋白与脂筏的关联性, 探讨干扰素诱导蛋白Viperin 抑制HCV 复制的机制。结果显示, 在体外HCV 亚基因复制子( replicon) 及感染细胞模型中过量表达Viperin 可显著降低细胞内HCV 非结构蛋白的表达及RNA 的水平。膜漂浮实验发现, 过量表达的Viperin 可通过干扰HCV 非结构蛋白NS3、NS5A 与细胞内脂筏膜的关联, 使其对非离子去污剂敏感。进一步研究发现, 与脂筏膜结构组成相关的法尼基合成酶( FPPS) 可通过与Viperin 相互作用, 部分反转Viperin 的抗HCV 复制效应。以上结果提出了一种新的干扰素抗HCV 机制, 即干扰素诱导蛋白Viperin 可通过影响非结构蛋白与脂筏的关联, 干扰HCV 复制复合体的稳定性, 从而抑制HCV 的复制。

Infection with hepatitis C virus (HCV) is currently treated with interferon-α( IFN-α) , but the molecular mechanismby which IFN inhibits HCV replication still remains elusive. Therefore, in this study, we attempted to elucidate the possible mechanismfor the IFN-inducible protein, Viperin, against HCV. Over-expression of Viper in could significantly down-regulate intracellular levels of HCV protein and RNA in both the replicon and HCVcc systems. Membrane flotation analysis indicated that expression of Viperin could interfere with the association of HCV NS3 and NS5A with the lipid raft, resulting in increased sensitivity of these two proteins to the treatment of non-ionic detergent. Furthermore, Viperinwas able to interact with FPPS because co-transfection of Viperin with FPPS could partially reverse the anti-HCV effects of Viperin in replicon cells. The above results indicate a possible novel mechanismof IFN-induced antiviral activity, that is, over-expression of Viperin can interfere with the microdomain of intracellular lipid raft and, therefore, further disrupt the stability of viral replicase complex to inhibit its functions.