Department of Infectious Diseases, Molecular Virology, Medical Facility, Heidelberg University, Heidelberg, Germany.
Gastroenterology. 2011 Sep;141(3):1057-66. doi: 10.1053/j.gastro.2011.06.010. Epub 2011 Jun 13.
BACKGROUND & AIMS: Hepatitis C virus (HCV) has a high propensity to establish persistence; better understanding of this process requires the development of a fully permissive and immunocompetent small animal model. Mouse cells can be engineered to express the human orthologs of the entry molecules CD81 and occludin to allow entry of HCV. However, RNA replication is poor in mouse cells, and it is not clear whether they support assembly and release of infectious HCV particles. We used a trans-complementation-based system to demonstrate HCV assembly competence of mouse liver cell lines.
A panel of 3 mouse hepatoma cell lines that contain a stable subgenomic HCV replicon was used for ectopic expression of the HCV structural proteins, p7, nonstructural protein 2, and/or apolipoprotein E (apoE). Assembly and release of infectious HCV particles was determined by measuring viral RNA, proteins, and infectivity of virus released into the culture supernatant.
Mouse replicon cells released low amounts of HCV particles, but ectopic expression of apoE increased release of infectious HCV to levels observed in the human hepatoma cell line Huh7.5. Thus, apoE is the limiting factor for assembly of HCV in mouse hepatoma cells but probably not in primary mouse hepatocytes. Products of all 3 human alleles of apoE and mouse apoE support HCV assembly with comparable efficiency. Mouse and human cell-derived HCV particles have similar biophysical properties, dependency on entry factors, and levels of association with apoE.
Mouse hepatic cells permit HCV assembly and might be developed to create an immunocompetent and fully permissive mouse model of HCV infection.
丙型肝炎病毒（HCV）具有高度持续感染的倾向；要更好地理解这一过程，就需要开发一种完全允许且具有免疫能力的小动物模型。可以通过工程改造使小鼠细胞表达 HCV 进入分子 CD81 和 occludin 的人同源物，从而允许 HCV 进入。然而，RNA 复制在小鼠细胞中较差，并且不清楚它们是否支持组装和释放具有感染性的 HCV 颗粒。我们使用基于转互补的系统来证明小鼠肝细胞系的 HCV 组装能力。
使用一组包含稳定亚基因组 HCV 复制子的 3 种小鼠肝癌细胞系，用于 HCV 结构蛋白 p7、非结构蛋白 2 和/或载脂蛋白 E（apoE）的异位表达。通过测量释放到培养上清液中的病毒 RNA、蛋白和感染性来确定传染性 HCV 颗粒的组装和释放。
小鼠复制子细胞释放的 HCV 颗粒数量较少，但 apoE 的异位表达将感染性 HCV 的释放增加到在人肝癌细胞系 Huh7.5 中观察到的水平。因此，apoE 是 HCV 在小鼠肝癌细胞中组装的限制因素，但在原代小鼠肝细胞中可能不是。所有 3 种人类 apoE 等位基因和小鼠 apoE 的产物都以相当的效率支持 HCV 组装。小鼠和人细胞衍生的 HCV 颗粒具有相似的物理特性、对进入因子的依赖性以及与 apoE 的关联水平。
小鼠肝细胞允许 HCV 组装，并且可能被开发用于创建具有免疫能力和完全允许的 HCV 感染的小鼠模型。
