HCV, Alcohol and Host Defense

HCV、酒精和宿主防御

• 批准号: 7114949
• 负责人: Gyongyi Szabo
• 金额: $ 38.82万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-15 至 2008-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7114949
• 关键词: CD14 molecule; CHO cells; RNase protection assay; alcoholism /alcohol abuse; chemokine; clinical research; dendritic cells; flow cytometry; gel mobility shift assay; genetically modified animals; hepatitis C virus; host organism interaction; human subject; immunoprecipitation; inflammation; laboratory mouse; leukocyte activation /transformation; macrophage; monocyte; polymerase chain reaction; protein structure function; toll like receptor; transfection; virus protein; western blottings

DESCRIPTION (provided by applicant): Alcohol use accelerates the progression of liver disease in chronic hepatitis C (HCV) infection; however, the interactions between alcohol and HCV have not yet been explored. Chronic HCV infection is associated with reduced HCV-specific immune responses, and alcohol use suppresses antigen-specific T cell activation via inhibition of monocyte and dendritic cell (DC) antigen presentation. Both chronic alcohol consumption and chronic HCV infection are independently associated with activation of inflammatory pathways that mediate hepatocellular injury. Thus, we hypothesize that alcohol, HCV interacts to activate non-specific pro-inflammatory cascades in chronic HCV infection, and this process may contribute to progression of liver damage. Based on our preliminary results, we propose that the pattern recognition receptor, toll-like receptor 2 (TLR2), mediates cellular activation by HCV core and NS3 proteins. We further postulate that alcohol may increase inflammatory cell activation by interacting with TLR2-mediated pathways. Our preliminary results show that myeloid DC (dendritic cells), the most potent antigen presenting cell type, have reduced T-cell activation capacity in patients with chronic HCV infection and this can be further decreased by alcohol treatment of DCs. Thus, we propose that alcohol contributes to the persistence of chronic infection in HCV by inhibiting functional maturation of dendritic cells, thereby decreasing antigen-specific T cell activation and viral recognition. The Specific Aims of this proposal are: 1. To investigate interactions between HCV- and alcohol-induced inflammatory pathways at the protein and mRNA levels and on activation of the nuclear regulatory kB/Rel pathway in normal monocytes and in patients with chronic HCV infection with and without alcohol use or chronic in vitro alcohol treatment. 2. To investigate the pattern recognition receptor, TLR2, as a putative receptor in cell activation by HCV proteins. This will be accomplished by testing cellular activation by HCV proteins in TLR2-transfected CHO and HEK cells and in macrophages of TLR2-deficient mice. The cooperation of TLR2 with other components of the TLR2 receptor complex required for successful transmission of HCV core and NS3 mediated cell activation will be identified by selectively investigating the roles of CD14, TLR 1, and TLR6. 3. To evaluate the interactions between alcohol and HCV proteins on TLR2-mediated cell activation pathways by determining the effects of acute and chronic alcohol treatment on TLR2 expression, gene activation, and TLR2-mediated monocyte activation from normal controls and chronic HCV infected patients. Investigation of downstream elements involved in TLR2-mediated intracellular signaling after stimulation with core and NS3 proteins and their modulation by alcohol will be tested. 4. To delineate the role of TLR2-mediated signaling by HCV core and NS3 proteins in the reduced dendritic cell differentiation in HCV infected patients and to evaluate the effect of alcohol on TLR2-mediated signals in DC development. Results from these studies should reveal molecular and cellular mechanisms by which alcohol interacts with HCV infection to accelerate disease persistence and progression.

描述（由申请人提供）：饮酒会加速慢性丙型肝炎（HCV）感染者肝病的进展；然而，酒精和丙型肝炎病毒之间的相互作用尚未得到探索。 慢性 HCV 感染与 HCV 特异性免疫反应降低有关，饮酒通过抑制单核细胞和树突状细胞 (DC) 抗原呈递来抑制抗原特异性 T 细胞活化。 慢性饮酒和慢性丙型肝炎病毒感染均与介导肝细胞损伤的炎症途径的激活独立相关。 因此，我们假设酒精和丙型肝炎病毒相互作用，激活慢性丙型肝炎病毒感染中的非特异性促炎症级联反应，这一过程可能导致肝损伤的进展。 根据我们的初步结果，我们提出模式识别受体 Toll 样受体 2 (TLR2) 通过 HCV 核心和 NS3 蛋白介导细胞激活。 我们进一步假设酒精可能通过与 TLR2 介导的途径相互作用来增加炎症细胞的活化。 我们的初步结果表明，髓样 DC（树突状细胞）是最有效的抗原呈递细胞类型，它降低了慢性 HCV 感染患者的 T 细胞活化能力，并且可以通过对 DC 进行酒精治疗来进一步降低这种能力。 因此，我们认为酒精通过抑制树突状细胞的功能成熟，从而减少抗原特异性 T 细胞激活和病毒识别，从而导致 HCV 慢性感染的持续存在。 该提案的具体目标是： 1. 研究正常单核细胞和慢性 HCV 感染患者中 HCV 和酒精诱导的炎症通路在蛋白质和 mRNA 水平上的相互作用以及核调节 kB/Rel 通路激活的相互作用。并且没有饮酒或长期体外酒精治疗。 2. 研究模式识别受体 TLR2 作为 HCV 蛋白激活细胞的推定受体。这将通过在 TLR2 转染的 CHO 和 HEK 细胞以及 TLR2 缺陷小鼠的巨噬细胞中测试 HCV 蛋白的细胞激活来实现。 通过选择性研究 CD14、TLR 1 和 TLR6 的作用，将确定 HCV 核心成功传播和 NS3 介导的细胞激活所需的 TLR2 与 TLR2 受体复合物其他成分的合作。 3.通过确定急性和慢性酒精治疗对正常对照和慢性HCV感染患者的TLR2表达、基因激活和TLR2介导的单核细胞激活的影响，评估酒精和HCV蛋白之间对TLR2介导的细胞激活途径的相互作用。将测试核心蛋白和 NS3 蛋白刺激后参与 TLR2 介导的细胞内信号转导的下游元件及其通过酒精的调节。 4. 描述 HCV 核心和 NS3 蛋白介导的 TLR2 信号在 HCV 感染患者树突状细胞分化减少中的作用，并评估酒精对 DC 发育中 TLR2 介导的信号的影响。 这些研究的结果应该揭示酒精与丙型肝炎病毒感染相互作用以加速疾病持续和进展的分子和细胞机制。