Tight Junction: Gate to HCV Tropism, Therapeutics and Pathogenesis

紧密连接：HCV 趋向性、治疗和发病机制的大门

• 批准号: 7943456
• 负责人: TONY WANG
• 金额: $ 30.14万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2015-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7943456
• 关键词: Accounting; Acute; Adverse effects; Affect; Animal Model; Antibodies; Antiviral Agents; Antiviral Therapy; CD81 gene; Cell Culture Techniques; Cell Line; Cell physiology; Cells; Chronic Hepatitis; Cirrhosis; Cleaved cell; Combined Modality Therapy; Complementary DNA; DNA Library; Data; Development; Down-Regulation; Endoplasmic Reticulum; Engineering; Evaluation; Fibroblasts; Future; Hepatic; Hepatitis C; Hepatitis C virus; Hepatocyte; Human; Immune; Individual; Infection; Infection prevention; Integration Host Factors; Laboratories; Lead; Life Cycle Stages; Light; Liver diseases; Maps; Mediating; Molecular; Molecular Biology; Monoclonal Antibodies; Morphology; Mus; NIH 3T3 Cells; Pathogenesis; Pathology; Patients; Peptides; Primary carcinoma of the liver cells; Proteins; Public Health; Recombinants; Reporting; Research; Resistance; Resistance to infection; Ribavirin; Rodent; Screening procedure; Small Interfering RNA; System; Testing; Therapeutic; Tight Junctions; Treatment Protocols; Vaccines; Viral; Virus; Work; base; cellular engineering; claudin-1 protein; env Gene Products; extracellular; global health; hepatitis C virus envelope 2 protein; hepatoma cell; immunoenhancing factor; inhibitor/antagonist; insight; interest; liver biopsy; novel; novel therapeutics; occludin; polyclonal antibody; prevent; public health relevance; receptor; vaccine candidate; virus envelope; virus tropism

DESCRIPTION (provided by applicant): Hepatitis C virus (HCV) exacts a heavy toll on global health by causing acute and chronic hepatitis, cirrhosis, as well as hepatocellular carcinoma. Paradoxical to this cold reality, there is no vaccine available to prevent the infection, and combination therapy with pegylated IFN-a and ribavirin is only effective in 40-80% of patients and has severe side effects. Fortunately, with the recently developed infectious clones, we are finally able to dissect the entire viral life cycle at the molecular level. It is conceivable that novel antiviral therapies and treatment regimens relieving HCV associated pathologies will become available within foreseeable future given the accelerated pace of research. As far as what this application concerns, accumulating evidence has highlighted the importance of tight junction (TJ) in HCV entry. Specifically, we and others reported that the tight junction protein occludin (OCLN) is indispensible for HCV envelope protein-dependent entry. Evidence also indicated that OCLN partially accounts for the narrow host range of HCV. However, murine cells expressing all known human (co-)receptors remained resistant to cell culture grown HCV (HCVcc) infection, suggesting either additional human factors are required or dominant inhibitors exist in murine cells. Interestingly, we observed that both OCLN and claudin-1 were downregulated in HCVcc-infected hepatoma cells. Subsequent study suggested that OCLN is increasingly cleaved in HCV infected cells. In light of these findings, we believe novel therapeutics, novel infection systems, and novel insights in understanding HCV-associated pathogenesis may be developed. We hypothesize that antibody against OCLN extracellular loops or OCLN-derived peptide may block the spreading of virus (to be tested in Aim 1); additional host factors are required to support optimal HCV infection in murine cells or restriction factors exist in these cells (to be tested in Aim 2); downregulation of TJ proteins during HCV entry may alter cell physiology (to be tested in Aim 3). We plan to test the hypotheses by (i) assessing the effect of antibodies against OCLN or OCLN-derived peptides on HCV entry. (ii) identifying host factors promoting or restricting HCV infection of murine cells. (iii) analyzing the impact of HCV infection on TJ integrity and hepatocyte functions. PUBLIC HEALTH RELEVANCE: HCV infection poses a serious threat to US public health and there is currently no vaccine available. Completion of the proposed research will shed lights to the development of novel therapeutics, small animal models, and to our understanding of HCV-associated pathogenesis.

描述（由申请人提供）：丙型肝炎病毒（HCV）可引起急性和慢性肝炎、肝硬化以及肝细胞癌，对全球健康造成严重损害。与这个冷酷的现实相反，没有疫苗可以预防感染，聚乙二醇化 IFN-a 和利巴韦林的联合治疗仅对 40-80% 的患者有效，并且具有严重的副作用。幸运的是，随着最近开发的感染性克隆，我们终于能够在分子水平上剖析整个病毒生命周期。可以想象，随着研究步伐的加快，在可预见的将来，缓解 HCV 相关病症的新型抗病毒疗法和治疗方案将变得可用。就本申请所涉及的内容而言，越来越多的证据强调了紧密连接 (TJ) 在 HCV 进入中的重要性。具体来说，我们和其他人报道紧密连接蛋白occludin (OCLN)对于HCV包膜蛋白依赖性进入是必不可少的。证据还表明，OCLN 部分解释了 HCV 宿主范围狭窄的原因。然而，表达所有已知人类（共）受体的鼠细胞仍然对细胞培养的 HCV (HCVcc) 感染具有抵抗力，这表明要么需要额外的人为因素，要么鼠细胞中存在显性抑制剂。有趣的是，我们观察到 OCLN 和 claudin-1 在 HCVcc 感染的肝癌细胞中均下调。随后的研究表明 OCLN 在 HCV 感染的细胞中被越来越多地裂解。根据这些发现，我们相信可能会开发出新的治疗方法、新的感染系统以及理解 HCV 相关发病机制的新见解。我们假设针对 OCLN 胞外环或 OCLN 衍生肽的抗体可能会阻止病毒的传播（将在目标 1 中进行测试）；需要额外的宿主因子来支持小鼠细胞中的最佳 HCV 感染，或者这些细胞中存在限制因子（将在目标 2 中进行测试）； HCV 进入期间 TJ 蛋白的下调可能会改变细胞生理学（将在目标 3 中进行测试）。我们计划通过 (i) 评估针对 OCLN 或 OCLN 衍生肽的抗体对 HCV 进入的影响来检验这些假设。 (ii)鉴定促进或限制HCV感染小鼠细胞的宿主因素。 (iii)分析HCV感染对TJ完整性和肝细胞功能的影响。 公共卫生相关性：HCV 感染对美国公共卫生构成严重威胁，目前尚无疫苗可用。拟议研究的完成将为新型疗法、小动物模型的开发以及我们对 HCV 相关发病机制的理解提供线索。