Mechanism for spread of a quasi-enveloped hepatotropic virus

准包膜嗜肝病毒的传播机制

基本信息

批准号：
10467064
负责人：
Zongdi Feng
金额：
$ 35.39万
依托单位：
RESEARCH INST NATIONWIDE CHILDREN'S HOSP
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-09-19 至 2024-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10467064
关键词：
Address Affect Antibodies Antibody Response Apical Bile fluid Blocking Antibodies Blood Blood Circulation Carrier Proteins Cell Culture System Cell Culture Techniques Cells Complex Data Diagnostic Ebola virus Enteral Enterovirus Enzymes FDA approved Feces Goals HIV Hepatitis A Hepatitis B Hepatitis E virus Hepatocyte Human Human poliovirus Immunity Immunocompromised Host Individual Infection Knowledge Lead Life Cycle Stages Liver Liver Fibrosis MTCH1 gene Mediating Membrane Modeling Morbidity - disease rate Multivesicular Body Mus Outcome Palmitic Acylation Site Pathogenesis Patients Persons Play Process Proteins Regulation Research Rhinovirus Role Serum Sorting - Cell Movement Support System Surface Testing Therapeutic Intervention Vaccines Viral Viral Antigens Viral Envelope Proteins Viral Pathogenesis Virion Virus Virus Diseases Work alanylproline antiviral drug development apical membrane basolateral membrane biliary tract chronic infection complement system env Gene Products improved in vivo insight mortality neutralizing antibody new therapeutic target novel overexpression palmitoylation particle prolyl-serine virus envelope

项目摘要

Summary Hepatitis E virus (HEV), an enterically transmitted virus, exists either as naked virions that are shed in the feces or quasi-enveloped virions that circulate in the blood. The quasi-envelopment of HEV facilitates noncytolytic release of virus from infected cells. However, the lack of viral envelope proteins raises question about mechanism for HEV spread and the role of antibodies in natural infection. HEV infects ~20 million people annually and causes significant morbidity and mortality. Persistent HEV infection in immunocompromised individuals can lead to rapid progression of liver fibrosis. Currently there are no FDA-approved diagnostics and HEV-specific therapies. Our long-term goal is to unravel the functional role(s) of this unusual envelopment in the virus life cycle and pathogenesis for the purpose of identifying novel targets for therapeutic intervention. The overall objective of this project is to understand the role of the quasi-envelopment in HEV spread and how it affects antibody-mediated neutralization. The viral ORF3 protein is known to play a key role in HEV envelopment. Our preliminary data suggest that ORF3 is subjected to regulation by palmitoylation to mediate virion release. In addition, we found evidence that neutralizing antibodies block HEV spread in cells that have already established infection. Our central hypothesis is that ORF3-mediated quasi-envelopment is required for HEV release into the bloodstream and into the bile (then shed into feces), and quasi-enveloped HEV particles mediate spread with the liver via a novel entry mechanism that is susceptible to post-entry neutralization by antibodies. We will test this hypothesis in polarized hepatocyte cell culture and in human liver chimeric mice. Aim 1 will define the role of palmitoylation of ORF3 in its cellular localization and function in virus release. Aim 2 will define the cellular requirements and role of ORF3 in HEV spread. Aim 2 will also define the role and mechanism of antibodies in blocking HEV spread. The expected outcomes of the proposed research are novel insights into the spread mechanism for a quasi- enveloped virus, and may have implications for other non-enveloped viruses such as hepatitis A, poliovirus, and enteroviruses that also become quasi-enveloped at certain stages of their life cycle. This work will fill gaps in our understanding of the quasi-envelopment processes and how it influences virus spread, pathogenesis and immunity.

概括肝炎病毒（HEV）是一种肠内传播的病毒，或者存在于粪便中脱落的病毒或在血液中循环的准发育病毒体。 HEV的准开发促进了非溶解的从感染细胞中释放病毒。但是，缺乏病毒包膜蛋白会提出有关机制的问题为了hev扩散和抗体在自然感染中的作用。 HEV每年感染约2000万人，并导致显着的发病率和死亡率。免疫功能低下的个体中持续的HEV感染会导致快速肝纤维化的进展。目前没有FDA批准的诊断和HEV特异性疗法。我们的长期目标是揭示病毒生命周期中这种异常信封的功能作用发病机理的目的是识别用于治疗干预的新靶标。总体目标项目是要了解准开发在HEV传播中的作用及其如何影响抗体介导的中和。众所周知，病毒ORF3蛋白在HEV包膜中起关键作用。我们的初步数据表明ORF3受棕榈酰化的调节以介导病毒粒子释放。此外，我们发现证据表明中和抗体阻止HEV扩散在已经建立感染的细胞中。我们的中心假设是ORF3介导的准开发是HEV释放到血液中需要的然后进入胆汁（然后脱落成粪便），准发达的HEV颗粒通过A介导的肝脏传播新的进入机制，容易受到抗体的入学后中和。我们将检验这个假设在极化的肝细胞培养和人肝脏嵌合小鼠中。 AIM 1将定义棕榈酰化的作用 ORF3在病毒释放中的细胞定位和功能中的作用。 AIM 2将定义细胞要求，并且 ORF3在HEV传播中的作用。 AIM 2还将定义抗体在阻断HEV扩散中的作用和机制。拟议的研究的预期结果是对准确机制的新颖见解包裹的病毒，可能对其他非发育病毒（例如乙型肝炎，脊髓灰质炎病毒和）有影响在其生命周期的某些阶段，肠病毒也成为准发型。这项工作将填补我们的空白理解准开发过程及其如何影响病毒传播，发病机理和免疫。