EPIDEMIC CHIKUNGUNYA VIRUS: MOSQUITO INFECTION DETERMINANTS

描述（由申请人提供）：本提案是根据PA-04-119提交的。它包括两个优先研究领域：“节肢动物病媒生物学”和“感染的自然史”。它建立在我们小组对基孔肯雅病毒（CHIKV）的不寻常的专业知识基础上，该病毒最近在留尼汪岛造成了255，000多例人类病例，在印度造成了100，000多例病例，并在从流行地区返回欧洲和中国的游客中造成了疾病。潜在的二次传播和建立一个传播周期，涉及白纹伊蚊和Ae。埃及人是一个可信的威胁，必须认真对待（Pearson，2006年）。本研究的长期目标是确定病毒糖蛋白与蚊子中肠细胞结合的机制，并研究这些相互作用如何决定/增强蚊子的病毒感染和传播。这些知识可能有助于抗病毒策略的制定。中心假设：病毒基因决定CHIKV和中肠细胞表面蛋白的相互作用，所述蛋白促进流行株LR 2006 OPY 12005通过Ae. aegypti和Ae.白纹蚊目标1：确定并比较从留尼旺岛获得的流行毒株CHIKV LR 2006 OPY 1和非洲中部毒株SG 41855的口服感染剂量50（OID 50）和感染动力学。aegypti和Ae.白纹蚊假设：目前在印度洋爆发的CHIKV的不寻常的毒力和规模是由于病毒基因组的变化，其导致蚊子中感染和传播的增强。目的2：开发表达EGFP的感染性克隆，并开发复制子系统以帮助确定Ae中CHIKV感染的位点。aegypti和Ae.白纹蚊感染性克隆技术将为在分子水平上研究甲病毒和蚊子的相互作用提供重要工具。目的3：鉴定Ae细胞表面受体蛋白。埃及蚊子对CHIKV的敏感性可以调节CHIKV蚊子感染性。假设：在Ae.埃及伊蚊导致感染和传播减少。创新、成果和益处：这项研究将提供当前流行病中急需的关于CHIKV的背景信息，并使我们能够生成进一步研究蚊子-病毒相互作用机制所需的工具和方案。Fauci等人，（2005）强调了与新出现的传染病相关的研究的重要性和价值，基孔肯雅病毒（CHIKV）是重新出现的病毒可能具有的重大公共卫生影响的一个很好的例子。持续的基孔肯雅热疫情已在印度洋留尼汪岛造成超过255，000例人间病例（占总人口的30%），在印度造成超过100，000例病例。拟议的研究将调查蚊子感染的机制，鉴定与CHIKV结合的蚊子中肠蛋白，并利用双链RNA方法结合新的分子工具来评估CHIKV在蚊子中的感染和传播动力学。

DESCRIPTION (provided by applicant): This proposal is submitted in response to PA-04-119. It encompasses two priority research areas: "biology of arthropod vectors" and "natural history of infection". It builds upon our groups unusual expertise on chikungunya virus (CHIKV), a virus that has recently caused over 255,000 human cases in La Reunion, over 100,000 cases in India, and disease in tourists returning from the endemic area to Europe and China. The potential for secondary spread and establishment of a transmission cycle involving Aedes albopictus and Ae. aegypti is a credible threat and must be treated seriously (Pearson, 2006). The long-term goal of this research is to identify the mechanism underlying the binding of viral glycoproteins to mosquito midgut cells and investigate how these interactions determine/enhance viral infection in, and transmission by mosquitoes. This knowledge may facilitate antiviral strategy development. Central Hypothesis: viral genes determine the interactions of CHIKV and midgut cell surface proteins that promote transmission of the epidemic strain LR2006 OPY1 2005 by Ae. aegypti and Ae. albopictus mosquitoes. Aim 1: To determine and compare oral infectious dose 50 (OID50)s and infection dynamics of the epidemic strain CHIKV LR2006 OPY1 obtained from La Reunion and of a Central African strain SG41855, in Ae. aegypti and Ae. albopictus mosquitoes. Hypothesis: the unusual virulence and magnitude of the current outbreak of CHIKV in the Indian Ocean is due to changes in the viral genome that cause enhanced infection in, and transmission by mosquitoes. Aim 2: To develop infectious clones which express EGFP and to develop a replicon system to aid in the determination of sites of CHIKV infection in Ae. aegypti and Ae. albopictus mosquitoes. Infectious clone technology will provide important tools to examine alphavirus and mosquito interactions at the molecular level. Aim 3: To identify putative cell surface receptor proteins in Ae. aegypti mosquitoes for CHIKV that can modulate CHIKV mosquito infectivity. Hypothesis: suppression of CHIKV-binding cell surface proteins expression levels in Ae. aegypti results in a decreased infection and dissemination. Innovation, outcomes, and benefits: This study will provide much needed background information on CHIKV from the current epidemic, and will allow us to generate tools and protocols required to further examine the mechanisms of mosquito-viral interactions. Fauci et al., (2005) highlighted the importance and value of research related to emerging infectious diseases, and chikungunya virus (CHIKV) is an excellent example of the substantial public health impact that a re-emerging virus can have. The ongoing epidemic of chikungunya has already caused over 255,000 human cases in the Indian Ocean island of La Reunion (>30% of the total population) and over 100,000 cases in India. The proposed research will investigate the mechanism of mosquito infection, identify mosquito midgut proteins that bind to CHIKV, and utilize a double-stranded RNA approach coupled with new molecular tools to evaluate infection, and dissemination dynamics of CHIKV in mosquitoes.