Developing Murine Models of HCV Replication

描述（由申请人提供）：全球约有2%的人口感染了丙型肝炎病毒（HCV），丙型肝炎病毒（HCV）已成为一个重大的公共卫生问题，造成了重大的医疗、社会和经济负担。70% - 90%的感染者不能清除病毒，并保持慢性感染，有可能发展为持续性肝炎、肝硬化和肝细胞癌（HCC）。因此，hcv相关的肝脏疾病是美国肝移植的主要原因。目前，没有可用的预防性疫苗，只有20-30%的慢性感染患者对目前可用的治疗有反应。因此，迫切需要一种预防性疫苗和替代治疗方案。不幸的是，由于缺乏强大的组织培养复制系统和小动物模型，研究工作难以理解并因此与这种感染作斗争。尽管最近体外HCV复制子系统的发展已经克服了这些局限性，但仍然需要小动物模型来研究病毒与宿主的相互作用，以评估病毒的病理作用，更好地了解HCV免疫学（例如恢复与持续的免疫学和病毒学基础），以及测试控制HCV感染的生理和药理学药物的体内潜力。因此，本探索性建议的目标是创建能够表达和潜在复制HCV的小鼠模型。最初的努力将集中在使用可选择的HCV复制子上，这已被证明是一种有效的HCV复制系统。然而，在这些研究中获得的小鼠适应信息可能随后允许开发复制原生HCV基因组的类似模型。具体目标是：1)确定HCV的物种趋向性是否可以通过使现有的HCV复制子在小鼠肝细胞中复制而改变；2)确定是否可以通过瞬时t7驱动HCV构建体在体内表达建立小鼠急性HCV模型；3)确定稳定的RNA聚合酶i驱动的HCV构建体表达是否可以作为HCV体内慢性小鼠模型。

DESCRIPTION (provided by applicant): With approximately 2% of the world population infected, Hepatitis C Virus (HCV) has emerged as a significant public health problem creating a significant medical, social, and economic burden. Between 70- 90% of those infected fail to clear the virus and remain chronically infected with the likelihood of progression to persistent hepatitis, liver cirrhosis, and hepatocellular carcinoma (HCC). As a result, HCV-associated liver disease is the leading cause of liver transplantation in the United States. At this time, no preventative vaccine is available, and only 20-30% of chronically infected patients respond to the currently available therapy. Hence, there is a pressing need for a preventative vaccine and alternative treatment options. Unfortunately, research efforts to understand, and thus combat, this infection have been hindered by the lack of robust tissue culture replication systems and small animal models. While the recent development of the in vitro HCV replicon system has overcome some of these limitations, small animal models are still needed for the study of viral-host interactions to assess the pathological effects of the virus and to better understand HCV immunology (e.g. the immunological and virological basis of recovery versus persistence), as well as for testing the in vivo potential of physiological and pharmacological agents for controlling HCV infection. Therefore, the objective of this exploratory proposal is to create mouse models capable of expressing, and potentially replicating, HCV. Initial efforts will focus on the use of selectable HCV replicons, which have proven to be an efficient HCV replication system. However, the mouse-adaptation information gained in these studies may subsequently allow for the development of analogous models that replicate native HCV genomes. The Specific Aims to be addressed are: 1) determine if HCV species tropism can be altered by adapting currently available HCV replicons to replicate in mouse hepatocytes; 2) determine if a murine model of acute HCV can be established by transient T7-driven expression of HCV construct(s) in vivo; and 3) determine if stable RNA Polymerase I-driven expression of HCV construct(s) can serve as a chronic murine model of HCV in vivo.