Host cell receptor variation and control of viral cross-species transmission

宿主细胞受体变异和病毒跨物种传播的控制

• 批准号: 8642015
• 负责人: Andrew Brownell Allison
• 金额: $ 5.51万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-03-15 至 2016-03-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8642015
• 关键词: Affinity; Amino Acids; Animal Testing Alternatives; Animals; Binding; Binding Sites; Biological Assay; Biological Models; Canine Parvovirus; Canis familiaris; Capsid; Capsid Proteins; Carnivora; Cells; Coyotes; Disease; Disease Outbreaks; Epidemic; Event; Evolution; Feline Parvovirus; Feline panleukopenia virus; Fluorescence Microscopy; Genes; Genetic; Genomics; Health; Human; In Transferrin; In Vitro; Infection; Laboratories; Maintenance; Mediating; Microfluidic Microchips; Microscopy; Modeling; Molecular Biology; Mutation; Parvovirus; Parvovirus Infections; Pathway interactions; Phylogenetic Analysis; Phylogeny; Play; Predisposition; Property; Proteins; Raccoon Dogs; Raccoons; Receptor Cell; Recording of previous events; Refractory; Relative (related person); Research; Resistance; Resistance to infection; Role; Site; Site-Directed Mutagenesis; Structure; Techniques; Testing; Training Programs; Transferrin Receptor; Variant; Viral; Virus; Virus Diseases; Virus Receptors; Wolves; base; genome sequencing; glycosylation; innovation; mutant; novel; pandemic disease; pathogen; prevent; public health relevance; receptor; receptor binding; transmission process

DESCRIPTION (provided by applicant): An important form of virus emergence is the cross-species transmission of a virus from its normal animal reservoir to a new animal and/or human host. My studies seek to identify the viral, host, and evolutionary mechanisms that governed the emergence of canine parvovirus (CPV) as a new pandemic pathogen. CPV emerged in dogs in the mid-1970s, and spread world-wide in 1978, and my sponsor (Parrish) laboratory showed that CPV is a variant of feline panleukopenia virus (FPV) and that a key host range barrier to FPV infection in dogs was the cell receptor, transferrin receptor type-1 (TfR). Only a few viral capsid changes allowed CPV to bind the canine TfR and infect canine cells, and this provides an excellent model for defining the molecular interactions that govern cross-species transmission, adaptation, and hence pathogen emergence. It is now also clear that other mammalian hosts can be infected by these parvoviruses and that those hosts likely played roles in the pandemic emergence of CPV. My proposed studies therefore seek to define the range of viral variants found in alternative animal hosts, to determine how these viruses adapt to specific hosts, and also to explain how interactions between the viruses and receptors determine successful cross-species infections. Aim 1: To determine the evolutionary history of CPV emergence as a pandemic pathogen and to define the roles of different hosts in the evolution and cross-species transmission of these viruses. We will isolate and comprehensively characterize viruses from various carnivore species to determine their roles as hosts in parvovirus evolution. Viruses will be characterized by genomic sequencing, phylogenetic analysis, antigenic studies, and replication assays in various host cells. Site-directed mutagenesis of key residue changes in the viruses will be used to test for their effects on viral structures and in controlling host range. Aim 2: To characterize and functionally test the TfRs from various hosts to clarify the role of viral receptor sequence and structural variation in determining susceptibility to parvovirus infection. We will clone and express the TfRs from various carnivore species and characterize receptor-binding properties for viruses (or viral mutants with specific changes) in microfluidic devices using total internal reflection fluorescence (TIRF) microscopy. Variation in host TfR sequences will be examined to identify evidence of positive selection of the receptors during the evolution of the hosts. Viruses grown in different host cells in vitro will be examined for capsid changes that alter receptor binding, where we will use deep genome sequencing to discern the rate and types of viral variation selected. These studies will allow us to uniquely determine the interplay between the viral capsid and host receptors that mediate cross-species transmission and emergence.

描述（由申请人提供）：病毒出现的一种重要形式是病毒从其正常动物储层传播到新动物和/或人类宿主。我的研究旨在识别控制犬小扇联病毒（CPV）作为一种新的大流行病原体的病毒，宿主和进化机制。 CPV在1970年代中期出现在狗中，并于1978年在全球范围内传播，而我的赞助商（Parrish）实验室表明，CPV是猫Panleukopenia病毒（FPV）的一种变体，并且狗是细胞受体，转移蛋白受体类型1（TFR），是狗FPV感染的关键宿主范围。只有少数病毒的衣壳变化允许CPV结合犬TFR和感染犬细胞，这为定义控制跨物种传播，适应性以及因此病原体出现的分子相互作用提供了出色的模型。现在也很明显，其他哺乳动物宿主可以被这些细节病毒感染，并且这些宿主可能在CPV的大流行出现中扮演角色。因此，我提出的研究试图定义替代动物宿主中发现的病毒变异范围，以确定这些病毒如何适应特定宿主，并解释病毒和受体之间的相互作用如何确定成功的跨物种感染。目标1：确定CPV出现的进化史，作为大流行病原体，并定义不同宿主在这些病毒的进化和跨物种传播中的作用。我们将隔离和全面地表征各种食肉动物物种的病毒，以确定它们作为细小病毒进化中宿主的作用。病毒的特征是基因组测序，系统发育分析，抗原研究和在各种宿主细胞中的复制测定。病毒关键残基变化的位置定向诱变将用于测试其对病毒结构和控制宿主范围的影响。 AIM 2：表征和功能测试来自各种宿主的TFR，以阐明病毒受体序列和结构变化在确定细小病毒感染的敏感性中的作用。我们将使用总内反射荧光在微流体设备中克隆并表达来自各种食肉动物物种的TFR，并表征微流体设备中病毒（或特定变化的病毒突变体）的受体结合特性 （TIRF）显微镜。将检查宿主TFR序列的变化，以确定宿主进化过程中受体阳性选择的证据。将检查在不同宿主细胞中生长的病毒，以改变受体结合的衣壳变化，我们将使用深基因组测序来辨别所选病毒变异的速率和类型。这些研究将使我们能够唯一确定介导跨物种传播和出现的病毒式衣壳和宿主受体之间的相互作用。