Identification of cellular factors that mediate HCV cell-to-cell spread

介导 HCV 细胞间传播的细胞因子的鉴定

• 批准号: 9232075
• 负责人: Susan L. Uprichard
• 金额: $ 7.55万
• 依托单位: LOYOLA UNIVERSITY CHICAGO
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-03-01 至 2019-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9232075
• 关键词: Accounting; Address; Antiviral Agents; Cell secretion; Cells; Chronic; Cirrhosis; Combined Modality Therapy; Data; Distant; Drug Costs; Drug Targeting; Escape Mutant; Fatty Liver; Fibrosis; General Population; Genes; Goals; Guidelines; HCV Cirrhosis; Hepatitis C; Immune; Infection; Inflammation; Insulin Resistance; Integration Host Factors; Interferons; Investigation; Knowledge; Liver; Maintenance; Mediating; Molecular; Pathogenesis; Pathway interactions; Patients; Pharmacology; Pilot Projects; Play; Population; Primary carcinoma of the liver cells; Process; Public Health; Publishing; Research; Resistance; Risk; Role; Route; Small Interfering RNA; Therapeutic; Travel; United States; United States Department of Veterans Affairs; Viral; Viral Drug Resistance; Viral Pathogenesis; Virion; Virus; Virus Assembly; Virus Diseases; claudin-1 protein; clinically relevant; design; extracellular; inhibitor/antagonist; insight; knock-down; neutralizing antibody; novel; particle; permissiveness; public health relevance; response; screening; synergism; tool; transmission process; treatment strategy; viral resistance; virology; virus host interaction

 DESCRIPTION (provided by applicant): Viral entry into permissive cells is the first step in establishing infection and is thus a common and often effective antiviral drug target. However, after replication and assembly of viral particles in the initially infected cell, many viruses suchas HCV can spread to infect additional cells by two routes: cell-free and cell-to-cell spread. Because cell-to-cell spread can be a factor in the establishment of persistent infections and has been implicated in the spread of viral escape mutants during antiviral treatment, elucidating the mechanism(s) of viral cell-to-cell spread provides an opportunity to not only further our understanding of this relatively understudied aspect of virology and pathogenesis, but also perhaps provide insight into global strategies for enhancing the barrier to antiviral resistance during treatment. This is relevant for hepatitis C virus (HCV) because while effective interferon-free direct acting antiviral therapeutic combinations are becoming available for the treatment of HCV, the risk of viral escape has not been determined in less than ideal compliance populations and the astronomical cost of these drugs makes them prohibitively expensive for the majority of the world's HCV-positive populations. To address both this HCV-specific and more general public health issue, our long term goals include elucidating the molecular mechanisms of cell-free and cell-to-cell HCV spread, assessing the role of cell-to-cell spread in the establishment and maintenance of chronic viral infections, and assessing how blocking viral cell- to-cell spread, or not, can impact the synergy potential and barrier to resistance of different combination therapy approaches. The more focused objective of this small pilot R03 proposal is to identify the host cell factors/pathways involved in HCV cell-to-cell spread through directed siRNA knockdown screening interrogating genes already known to be involved in cell-free viral egress from the producer cell or cell-free entry into a target cells. While we already know that cell-free and cell-to-cell entry share some of the same factors and mechanisms (e.g. SRB1, CLDN1, OCLN), we have preliminary data identifying differentially required entry factors. More uniquely, we have also found that certain cellular factors required for the egress of cell-free infectious virus particles, are not required for the cell-to-cell spread. Hence, we hypothesize tha while there are some commonalities between cell-free and cell-to-cell spread, that there key mechanistic differences. Importantly, once identified, these differences can be exploited both as research tools and to develop effective antiviral strategies. As such, this pilot study will provid the fundamental information needed to enable the design of more in-depth mechanistic studies of these critical virus-host interactions and to determine whether factors involved in both routes of spread can serve as highly effective antiviral targets that enhance the barrier to viral resistance, a broad clinically relevant issue for the treatment of viral infections.

 描述（由申请人提供）：病毒进入允许细胞是建立感染的第一步，因此是一种常见且通常有效的抗病毒药物靶标。然而，在最初感染的细胞中复制和组装病毒颗粒后，许多病毒（如HCV）可以通过两种途径传播感染其他细胞：无细胞传播和细胞间传播。由于细胞间传播可能是建立持续感染的一个因素，并且在抗病毒治疗期间与病毒逃逸突变体的传播有关，因此阐明病毒细胞间传播的机制不仅为我们进一步理解病毒学和发病机制的这一相对不足的方面提供了机会，而且还可能为在治疗过程中增强抗病毒耐药性屏障的全球策略提供见解。这与丙型肝炎病毒（HCV）相关，因为虽然有效的无干扰素直接作用抗病毒治疗组合正变得可用于治疗HCV，但在不太理想的依从性人群中尚未确定病毒逃逸的风险，并且这些药物的天文数字的成本使得它们对于世界上大多数HCV阳性人群来说过于昂贵。为了解决这种HCV特异性和更普遍的公共卫生问题，我们的长期目标包括阐明无细胞和细胞间HCV传播的分子机制，评估细胞间传播在慢性病毒感染的建立和维持中的作用，以及评估阻断病毒细胞间传播，可以影响不同联合治疗方法的协同潜力和耐药性屏障。这个小型试验R 03提案的更集中的目标是通过定向siRNA敲低筛选来鉴定参与HCV细胞间传播的宿主细胞因子/途径，所述定向siRNA敲低筛选询问已知参与无细胞病毒从生产细胞流出或无细胞进入靶细胞的基因。虽然我们已经知道无细胞和细胞间进入共享一些相同的因子和机制（例如SRB 1，CLDN 1，OCLN），但我们有初步数据确定差异所需的进入因子。更独特的是，我们还发现无细胞感染性病毒颗粒外出所需的某些细胞因子对于细胞间传播是不需要的。因此，我们假设虽然无细胞和细胞间传播之间存在一些共同点，但存在关键的机制差异。重要的是，一旦确定，这些差异既可以作为研究工具，也可以开发有效的抗病毒策略。因此，这项初步研究将提供所需的基本信息，使设计更深入的机制研究这些关键的病毒-宿主相互作用，并确定是否涉及两种传播途径的因素可以作为高度有效的抗病毒靶点，增强病毒耐药性的障碍，一个广泛的临床相关问题，用于治疗病毒感染。