Cellular Immune Response to Acute HCV Infection

项目1的主要目的是确定与病毒持续存在相关的HCV特异性CDS T细胞功能受损的机制。虽然T细胞表位内的病毒逃逸突变发生在HCV免疫逃逸中，但慢性感染受试者中相当大比例的CDS T细胞识别不显示逃逸突变的HCV表位。因此，非逃逸表位特异性CDS细胞的功能损伤可能是HCV持续存在的另一个重要因素。我们建议对清除HCV感染的患者与未清除HCV感染的患者之间HCV特异性CDS T细胞表型5 TDe和功能进行全面的比较分析，并在识别发生置换的表位的T细胞与未发生置换的T细胞之间进行比较分析，以揭示与病毒持续存在相关的T细胞无反应性的特定分子和细胞机制。具体地说，我们的目标是：1）进行一组体外功能分析，评估各种先前表征的表型的HCV特异性CDS T细胞产生相关效应细胞因子和执行杀伤功能的能力; 2）开发和表征体内细胞毒性淋巴细胞（CTL）测定，用于使用过继转移到已建立的NOD/SCID/CD 4/CD 4/CD系统这将允许我们直接分析靶向人HCV特异性CDS T细胞上潜在相关细胞膜受体的抗体和/或细胞因子的体内功能效应。使用特异性拮抗剂抗体，候选分子决定CDS T细胞无反应性将在这种新的体内系统中，其中从患者的人T细胞过继转移到接受性免疫缺陷小鼠的审问。这种询问的结果将有直接的翻译相关的慢性HCV感染的免疫治疗，以及增强与持续感染相关的T细胞损伤的理解。项目2的体液免疫应答研究结果将被整合，以扩大人类对HCV的体液和细胞免疫应答之间相互作用的知识。我们 我们已经证明，我们可以获得这项研究所需的关键标本，并将能够进行独特的纵向研究，在急性丙型肝炎病毒的适应性免疫反应。

The primary objective of Project 1 is to define the mechanisms of functional impairment of HCV-specific CDS T cells associated with viral persistence. While viral escape mutations within T cell epitopes occur in HCV immune evasion, a significant proportion of CDS T cells in chronically infected subjects recognize HCV epitopes that do not demonstrate escape mutations. It is thus likely that functional impairment of CDS cells specific for nonescaped epitopes is an additional important factor in HCV persistence. We propose that a comprehensive comparative analysis of HCV-specific CDS T cell phenot5TDe and function among patients who clear HCV infection versus those who do not, and between T cells recognizing epitopes that undergo substitution and those that do not will reveal specific molecular and cellular mechanisms of T cell unresponsiveness relevant to viral persistence. Specifically, we aim l)To perform a set of in vitro fiinctional analyses assessing the capacity of HCV specific CDS T cells of various previously characterized phenotj^jes to produce relevant effector cj^okines and to perform killer functions and 2)To develop and characterize an in vivo cj^otoxic lymphocyte (CTL) assay for functional analysis of tetramer+ HCV specific CDS cells using adoptive transfer into an established NOD/SCID/--/- system. This will allow us to directly analyze the in vivo functional effects of antibodies and/or cytokines targeted at potentially relevant cell membrane receptors on human HCV specific CDS T cells. Using specific antagonist antibodies, candidate molecular determinants of CDS T cell unresponsiveness will be interrogated in this novel in vivo system in which human T cells from patients are adoptively transferred into receptive immunodeficient mice. Outcomes of this interrogation will have direct translational relevance to the immunotherapy of chronic HCV infection as well as enhancing understanding of T cell impairment associated with persistent infection. Results of studies of humoral immune responses from Project 2 will be integrated to expand knowledge of the interplay between humoral and cellular immune responses to HCV in humans. We have already demonstrated that we can obtain the critical specimens required for this investigation and will be able to conduct unique longitudinal studies of adaptive immune responses in acute HCV.