Role of HIV-1 Nef in Acceleration of HCV-Mediated Liver Disease

HIV-1 Nef 在加速 HCV 介导的肝病中的作用

• 批准号: 8797316
• 负责人: In-Woo Park
• 金额: $ 33.61万
• 依托单位: UNIVERSITY OF NORTH TEXAS HLTH SCI CTR
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-02-05 至 2017-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8797316
• 关键词: Acceleration; Acquired Immunodeficiency Syndrome; Biological; Biological Markers; Biological Process; Blood Transfusion; Boxing; Cell Line; Cell surface; Cells; Clinical; Coculture Techniques; Complex; Country; DNA; Data; Detection; Deterioration; Development; Disease; Disease Progression; Ethanol; Fostering; Frequencies; Genes; Genomics; Goals; HIV; HIV-1; Health; Hepatitis C; Hepatitis C virus; Hepatocyte; Human; Immune; Indium; Indolent; Infection; Jurkat Cells; Lipids; Liver; Liver diseases; Malignant Neoplasms; Mediating; Mediation; Mitogen-Activated Protein Kinases; Molecular; Molecular Biology; Morbidity - disease rate; Natural History; Pathogenesis; Patients; Phosphotransferases; Predisposition; Primary carcinoma of the liver cells; Production; Prognostic Marker; Proteins; Publications; Reactive Oxygen Species; Replicon; Reporting; Role; Route; SR-BI receptor; Signaling Molecule; Staging; T-Lymphocyte; Therapeutic; Tissue Sample; Tissues; Up-Regulation; Viral; Viral Load result; Viral Proteins; Virus; Virus Replication; adverse outcome; base; cholesterol trafficking; clinically relevant; co-infection; intravenous drug use; mortality; nef Protein; outcome forecast; success; tool; transmission process

DESCRIPTION (provided by applicant): HIV-1 is known to aggravate HCV-related liver disease by accelerating HCV replication through as yet unclear mechanisms. Recent studies indicate that HIV-1 Nef can be transferred from HIV-1 susceptible cells to other uninfected susceptible and even to non-susceptible cells through conduits or exosomes. Further, Nef possesses multiple exacerbating functions including intracellular lipid mediation of HCV replication, complexing with cancer-modulating cellular kinases, and interference with anti-HCV host immune defenses. Accordingly, we have studied the role of Nef in HCV-infected hepatocytes to better understand the pathobiology of co- infection. Our data showed that hepatocytes do not support HIV replication. No evidence of virus replication was observed, even when the HIV-1-transfected hepatocytes were co-cultured with Jurkat T cells, indicating that liver deterioration in the co-infected patient is not due to the replication of HIV-1 in the hepatocytes of the HCV infected host. Instead, HIV-1 Nef protein was found to be transferred from expressing T cells to hepatocytes through conduits, wherein up to 16% of hepatocytes harbor the transferred Nef by co-cultivation with nef-expressing Jurkat cells for 24 hr. Moreover, Nef altered the size and numbers of lipid droplets (LD) and consistently up-regulated HCV replication by 1.5~2.5 fold in the target hepatocytes, which is significant in view of the otherwis indolent baseline replication. Nef also dramatically augmented reactive oxygen species (ROS) production, which can activate signaling molecules, such as MAP kinase, to induce TGF¿1 expression. Besides, Nef increased intracellular and cell surface expression of scavenger receptor B1 (SR-B1), which is integral for virus entry and cholesterol trafficking in Huh7.5.1, implying that Nef can foster susceptibility of HCV infection in non-HCV infected hepatocytes. Further, Nef enhanced ethanol-mediated up-regulation of HCV replication so as to accelerate hepatocellular carcinoma (HCC). Taken together, these data indicate that HIV-1 Nef is a critical element in accelerating HCV-mediated liver pathogenesis via enhancing HCV replication and coordinating modulation of key intra- and extra-cellular molecules for liver decay. Based on these preliminary findings, we propose three Specific Aims for this project. Success in achieving these goals will clarify the pathobiologic mechanisms of HIV-1-mediated exacerbation of liver decay, leading to more effective tools for prognosis and therapeutics against dual virus hepatic disease.

描述（由申请人提供）：已知HIV-1可通过尚不清楚的机制加速HCV复制，从而加重HCV相关肝病。最近的研究表明，HIV-1 Nef可以通过管道或外泌体从HIV-1易感细胞转移到其他未感染的易感细胞，甚至转移到非易感细胞。此外，Nef具有多种加重功能，包括HCV复制的细胞内脂质介导，与癌症调节细胞激酶复合，以及干扰抗HCV宿主免疫防御。因此，我们研究了Nef在HCV感染的肝细胞中的作用，以更好地理解共感染的病理生物学。我们的数据显示肝细胞不支持HIV复制。即使当HIV-1转染的肝细胞与Jurkat T细胞共培养时，也没有观察到病毒复制的证据，表明共感染患者的肝脏恶化不是由于HCV感染宿主的肝细胞中HIV-1的复制。相反，发现HIV-1 Nef蛋白通过导管从表达T细胞转移到肝细胞，其中高达16%的肝细胞携带转移的Nef，通过与表达Nef的Jurkat细胞共培养24小时。此外，Nef改变了靶肝细胞中脂滴（LD）的大小和数量，并持续上调HCV复制1.5~2.5倍，这对于其他惰性基线复制是重要的。Nef还显著增加了活性氧（ROS）的产生，这可以激活信号分子，如MAP激酶，以诱导TGF β 1的表达。此外，Nef增加了细胞内和细胞表面清道夫受体B1（SR-B1）的表达，这是Huh 7.5.1中病毒进入和胆固醇运输所必需的，这意味着Nef可以促进非HCV感染肝细胞对HCV感染的易感性。此外，Nef增强乙醇介导的HCV复制上调，从而加速肝细胞癌（HCC）。综上所述，这些数据表明，HIV-1 Nef是通过增强HCV复制和协调调节肝衰变的关键细胞内和细胞外分子来加速HCV介导的肝脏发病机制的关键因素。根据这些初步的研究结果，我们提出了三个具体目标，为这个项目。成功实现这些目标将阐明HIV-1介导的肝衰恶化的病理生物学机制，从而为双重病毒肝病的预后和治疗提供更有效的工具。