Super-infection and virus spread during chronic hepadnaviral infection

慢性肝炎病毒感染期间的重复感染和病毒传播

• 批准号: 9022435
• 负责人: Severin O Gudima
• 金额: $ 31.99万
• 依托单位: UNIVERSITY OF KANSAS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-04-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9022435
• 关键词: Address; Affect; Antibodies; Antiviral Agents; Appearance; Area; Binding; Cells; Chronic; Chronic Hepatitis B; Clonal Expansion; Complex; Data; Development; Drug resistance; Duck Hepatitis B Virus; Event; Exclusion; Foundations; Goals; Hepadnaviridae; Hepatitis B Virus; Hepatocyte; Human; Immune system; In Vitro; Infection; Infection Control; Kinetics; Liver; Maintenance; Malignant Epithelial Cell; Modeling; Mutation; Non-Malignant; Pan Genus; Pathogenesis; Pharmaceutical Preparations; Population; Predisposition; Primary Infection; Primary carcinoma of the liver cells; Reporting; Risk; Risk Factors; Serum; Time; Viral; Viral Genome; Viral hepatitis; Viremia; Virion; Virus; Virus Diseases; Virus Receptors; Woodchuck; Woodchuck Hepatitis B Virus; improved; in vivo; inhibitor/antagonist; mutant; novel therapeutics; prototype

DESCRIPTION (provided by applicant): Hepatitis B virus (HBV) is a prototype hepadnavirus with 400 million chronic carriers worldwide. Chronic HBV infection is a main risk factor of hepatocellular carcinoma (HCC), causing >50% of all HCCs. Early in infection, HBV spreads virtually throughout the entire liver, but during chronic infection, areas of apparently virus-free hepatocytes (20-90% of the entire hepatocyte population) appear regardless of the ongoing viremia. These findings were made in HBV-infected humans and chimpanzees and in woodchucks infected with the woodchuck hepatitis virus (WHV), which is closely related to HBV. These observations, along with the analysis of kinetics of the emergence of drug-resistant HBV mutants, laid the foundation for a long-standing unresolved argument in the HBV field that in chronic infection, cell-to-cell spread of a hepadnavirus is at least very inefficient (if it occursat all), and super-infection is an unlikely event. It was proposed that chronic hepadnavirus infection can be maintained exclusively via division of the infected hepatocytes in the absence of the spread. Super-infection exclusion was shown for HBV-related duck hepatitis B virus (DHBV), and was suggested for HBV and WHV. However, the absence of the viral cell-to-cell spread and super-infection in chronic infections with either WHV or HBV has not been confirmed or dismissed. Therefore, in Aim 1, we propose to determine directly whether the cell-to-cell spread of hepadnavirus and super-infection of already infected cells occur during chronic infection, which would indicate that spread could be an essential factor for maintenance of chronic infection and thus could also be a so far unrecognized risk factor of HCC. In addition, HCCs are also frequently reported as being apparently virus-free in HBV carrier humans and WHV carrier woodchucks, suggesting that HCCs arise from altered hepatocytes that have lost the ability to support efficient hepadnavirus replication, and thus have a selective advantage for a clonal expansion since they are no longer targeted by the immune system. This has led us to Aim 2 that will determine (i) if hepadnavirus-induced HCC is still susceptible to infection with a hepadnavirus, and (ii) what controls the apparent virus-free status of HCC. We propose to use an invaluable surrogate model to study HBV infection and especially HCC development - WHV carrier woodchucks. We will super-infect WHV carriers with early HCCs with a different natural infectious WHV strain, WHVNY, which has a unique deletion and thus can be easily discriminated from the strain WHV7 used for the primary infection. We will (i) directly determine the susceptibility of normal hepatocytes and HCCs to WHVNY super-infection; and (ii) address if the immune system controls the ability of cells to get re-infected. Overall, the proposed study will greatly improve our understanding of the mechanism of chronic hepadnavirus infection in relation to HCC development. It has the potential to identify infectivity of virions and virus spred as important factors of pathogenesis and HCC risk, and may facilitate the use of entry inhibitors that bind the HBV receptor and block virus spread as new therapeutics for battling chronic HBV infection and reducing HCC risk.

描述（由申请人提供）：乙型肝炎病毒（HBV）是一种原型嗜肝DNA病毒，全世界有4亿慢性携带者。慢性 HBV 感染是肝细胞癌 (HCC) 的主要危险因素，导致超过 50% 的 HCC。在感染早期，乙型肝炎病毒几乎传播到整个肝脏，但在慢性感染期间，明显无病毒的区域 无论是否存在病毒血症，都会出现肝细胞（占整个肝细胞群的 20-90%）。这些发现是在感染 HBV 的人类和黑猩猩以及感染土拨鼠肝炎病毒 (WHV) 的土拨鼠中得出的，该病毒与 HBV 密切相关。这些观察结果，以及对耐药 HBV 突变体出现的动力学分析，为 HBV 领域长期悬而未决的争论奠定了基础，即在慢性感染中，嗜肝DNA病毒的细胞间传播至少是非常低效的（如果确实发生的话），并且重复感染是不太可能发生的事件。有人提出，慢性肝炎病毒感染 在没有传播的情况下，只能通过受感染肝细胞的分裂来维持。对 HBV 相关鸭乙型肝炎病毒 (DHBV) 进行了重复感染排除，并建议对 HBV 和 WHV 进行重复感染排除。然而，WHV 或 HBV 慢性感染中不存在病毒细胞间传播和重复感染尚未得到证实或驳回。因此，在目标1中，我们建议直接确定慢性感染过程中是否发生嗜肝DNA病毒的细胞间传播和已感染细胞的重复感染，这表明传播可能是维持慢性感染的重要因素，因此也可能是迄今为止未被认识的HCC危险因素。此外，据报道，在 HBV 携带者和 WHV 携带者土拨鼠中，HCC 明显不含病毒，这表明 HCC 是由改变的肝细胞产生的，这些肝细胞已经失去了支持高效肝炎病毒复制的能力，因此具有克隆扩增的选择性优势，因为它们不再是免疫系统的目标。这引导我们实现目标 2，即确定 (i) 嗜肝DNA病毒诱导的 HCC 是否仍然容易感染嗜肝DNA病毒，以及 (ii) 是什么控制着 HCC 的表观无病毒状态。我们建议使用一种宝贵的替代模型来研究 HBV 感染，尤其是 HCC 的发展 - WHV 携带者土拨鼠。我们将用不同的天然感染性 WHV 毒株 WHVNY 重复感染患有早期 HCC 的 WHV 携带者，该毒株具有独特的缺失，因此可以很容易地将其与用于原发感染的 WHV7 毒株区分开来。我们将 (i) 直接测定正常肝细胞和 HCC 对 WHVNY 重复感染的易感性； (ii) 解决免疫系统是否控制细胞再次感染的能力。总体而言，拟议的研究将极大地提高我们对慢性肝炎病毒感染与 HCC 发展相关机制的理解。它有可能确定病毒粒子和病毒传播的感染性是发病机制和 HCC 风险的重要因素，并可能促进使用结合 HBV 受体并阻止病毒传播的进入抑制剂作为对抗慢性 HBV 感染和降低 HCC 风险的新疗法。

项目成果

Structural and nucleic acid binding properties of hepatitis delta virus small antigen.

• DOI: 10.5501/wjv.v6.i2.26
• 发表时间: 2017-05-12
• 期刊: World journal of virology
• 作者: Alves, Carolina;Cheng, Hong;Cunha, Celso
• 通讯作者: Cunha, Celso

Agonistic Activation of Cytosolic DNA Sensing Receptors in Woodchuck Hepatocyte Cultures and Liver for Inducing Antiviral Effects.

• DOI: 10.3389/fimmu.2021.745802
• 发表时间: 2021
• 期刊: Frontiers in immunology
• 影响因子: 7.3
• 作者: Suresh M;Li B;Huang X;Korolowicz KE;Murreddu MG;Gudima SO;Menne S
• 通讯作者: Menne S

Hepatitis delta virus: A fascinating and neglected pathogen.

• DOI: 10.5501/wjv.v4.i4.313
• 发表时间: 2015-11-12
• 期刊: World journal of virology
• 作者: Cunha, Celso;Tavanez, Joao Paulo;Gudima, Severin
• 通讯作者: Gudima, Severin

Superinfection with woodchuck hepatitis virus strain WHVNY of livers chronically infected with strain WHV7.

土拨鼠肝炎病毒 WHVNY 株重复感染慢性感染 WHV7 株的肝脏。

• DOI: 10.1128/jvi.02361-14
• 发表时间: 2015
• 期刊: Journal of virology
• 影响因子: 5.4
• 作者: Rodrigues,Louise;Freitas,Natalia;Kallakury,BhaskarV;Menne,Stephan;Gudima,SeverinO
• 通讯作者: Gudima,SeverinO

Down-regulation of hepatitis delta virus super-infection in the woodchuck model.

土拨鼠模型中丁型肝炎病毒重复感染的下调。

• DOI: 10.1016/j.virol.2019.03.002
• 发表时间: 2019
• 期刊: Virology
• 影响因子: 3.7
• 作者: Lukash,Tetyana;Freitas,Natalia;Menne,Stephan;Gudima,SeverinO
• 通讯作者: Gudima,SeverinO