Viral and Host Determinants of Chikungunya Virus Dissemination

基孔肯雅病毒传播的病毒和宿主决定因素

基本信息

批准号：
10056971
负责人：
Kathryn Semmens Carpentier
金额：
$ 4.57万
依托单位：
UNIVERSITY OF COLORADO DENVER
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：
2018-11-01 至 2021-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10056971
关键词：
Acute Acute Disease Alphavirus Americas Amino Acids Animal Model Antiviral Agents Arboviruses Arthralgia Arthritis Asia Biochemical Blood Circulation Cell Culture Techniques Cells Chikungunya virus Chronic Chronic Disease Culicidae Data Development Dichloromethylene Diphosphonate Disease Disease Outbreaks Disease Outcome Epidemic Europe Event Far East Fever Genetic Polymorphism Glycoproteins Human ITGAX gene Immune response Immunohistochemistry In Situ Hybridization Indian Ocean Individual Infection Innate Immune Response Integration Host Factors Interferon Type I Interferons Intravenous Knowledge Laboratories Link Liposomes Mediating Mouse Strains Mus Mutate Mutation O&apos nyong-nyong virus Pathogenicity Patients Phagocytes Phase Population Positioning Attribute Property Proteins Rag1 Mouse Reporting Research Rheumatism Role Serum Site Spleen Splenic Red Pulp Structure Symptoms Testing Vaccines Viral Viral Pathogenesis Viremia Virion Virus Virus Diseases adaptive immune response base cell type chikungunya infection chronic infection glycosylation human model human pathogen improved insight macrophage mouse model mutant nonhuman primate particle prevent response therapeutic development tool virus host interaction

项目摘要

PROJECT SUMMARY Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes epidemics of severe rheumatologic disease. The impact of CHIKV disease extends globally, with recent outbreaks occurring in Asia, Europe and the Americas. Up to 50% of patients report persistent rheumatologic symptoms, with incapacitating arthralgia lasting for months to years after infection. Chronic disease has been linked in humans and animal models with persistent CHIKV infection. Despite this, the host-viral interactions that dictate viral clearance or persistence are poorly defined. To identify adaptive mutations associated with chronic CHIKV infection, the Morrison laboratory isolated CHIKV from the circulation of a chronically-infected Rag1-/- mouse. This virus contained a mutation in the E2 glycoprotein (E2 K200R) that dramatically enhances viremia and viral dissemination in WT mice, leading to more severe disease outcomes. Moreover, introduction of an E2 K200R mutation into additional CHIKV strains or a closely related alphavirus, o'nyong nyong virus, also enhances viremia, demonstrating this mutation evades a host response that is operative against multiple alphaviruses. High viremia in humans and non-human primates infected with CHIKV has been associated with more severe acute disease and an increased potential for chronic disease. Therefore, this mutant virus provides a valuable tool to identify host and viral determinants of alphavirus dissemination and pathogenicity. The enhanced dissemination mediated by CHIKV E2 K200R (CHIKVE2 K200R) is independent of type I IFN, demonstrating that additional innate immune responses significantly contribute to CHIKV control. My preliminary data demonstrates that WT CHIKV particles are rapidly cleared from the circulation following intravenous inoculation, while CHIKVE2 K200R particles remain stably detectable. Depletion of phagocytic cells prevents clearance of WT CHIKV from the circulation, but has no impact on the circulating levels of CHIKVE2 K200R. These findings reveal a critical role for phagocytic cells in controlling WT CHIKV dissemination and suggest that CHIKVE2 K200R evades clearance by phagocytic cells. My objective is to define the phagocytic cells that are responsible for CHIKV clearance, and to define the viral determinants of clearance and escape. Based on my preliminary data, I hypothesize that splenic red pulp macrophages efficiently capture WT CHIKV, and that CHIKVE2 K200R evades this response by abrogating interactions with a conserved residue in the E1 glycoprotein, resulting in structural alterations that facilitate evasion of phagocytic cells. In Aim 1, I will precisely define the population of phagocytic cells that mediate CHIKV clearance from the circulation. In Aim 2, I will define viral determinants that mediate CHIKV clearance by phagocytic cells or escape of this clearance mechanism. The proposed research will significantly advance the field by defining new mechanisms of host control of alphavirus dissemination, and viral determinants of escape.

项目摘要 Chikungunya病毒（Chikv）是一种蚊子传播的α病毒，导致严重的流行病风湿病。 CHIKV疾病的影响在全球范围内扩展，最近发生的爆发发生在亚洲，欧洲和美洲。多达50％的患者报告持续性风湿病症状，感染后数月至数年的关节对肢管的丧失能力。慢性病已与人类联系在一起和具有持续性CHIKV感染的动物模型。尽管如此，决定病毒的宿主病毒相互作用清除或持久性的定义很差。识别与慢性CHIKV相关的自适应突变感染，莫里森实验室从慢性感染的rag1 - / - 小鼠的循环中分离出CHIKV。该病毒在E2糖蛋白（E2 K200R）中含有突变，可显着增强病毒血症和病毒 WT小鼠的传播，导致更严重的疾病结局。此外，引入E2 K200R 突变成其他CHIKV菌株或密切相关的α病毒，O'Nyong Nyong病毒，也可以增强证明这种突变的病毒血症逃避了针对多个α病毒的宿主反应。感染CHIKV的人类和非人类灵长类动物的高病毒血症与更严重急性疾病和慢性疾病的潜力增加。因此，这种突变病毒提供了有价值的识别α病毒传播和致病性的宿主和病毒决定因素的工具。增强 Chikv E2 K200R（Chikve2 K200R）介导的传播独立于I型IFN，证明其他先天免疫反应显着有助于控制CHIKV。我的初步数据证明静脉注射后从循环中迅速清除了wt chikv颗粒接种，而Chikve2 K200R颗粒仍然可以稳定地检测到。吞噬细胞的耗竭阻止从循环中清除WT Chikv，但对Chikve2 K200R的循环水平没有影响。这些发现揭示了吞噬细胞在控制WT CHIKV传播中的关键作用，并建议 Chikve2 K200R逃避了吞噬细胞的清除。我的目标是定义吞噬细胞负责CHIKV清除，并定义清除和逃生的病毒决定因素。基于我初步数据，我假设脾脏红色的果实巨噬细胞有效地捕获了wt chikv，并且 Chikve2 K200R通过废除与E1糖蛋白中保守残基的相互作用，逃避了这种反应，导致结构性改变，促进吞噬细胞的逃避。在AIM 1中，我将精确定义从循环中介导CHIKV清除率的吞噬细胞种群。在AIM 2中，我将定义病毒通过吞噬细胞介导CHIKV清除或逃脱这种清除机制的决定因素。这拟议的研究将通过定义α病毒宿主控制的新机制大大推动该领域逃生的传播和病毒决定因素。