EPIDEMIC CHIKUNGUNYA VIRUS: MOSQUITO INFECTION DETERMINANTS

描述（由申请人提供）：本提案是针对PA-04-119提交的。它包括两个重点研究领域：“节肢动物媒介生物学”和“感染的自然史”。它以我们小组在基孔肯雅病毒（CHIKV）方面不同寻常的专业知识为基础。基孔肯雅病毒最近在留尼汪岛造成25.5万多人感染，在印度造成10万多人感染，并在从流行地区返回欧洲和中国的游客中感染。白纹伊蚊和伊蚊可能发生二次传播并形成传播周期。埃及伊蚊是一种可信的威胁，必须认真对待（Pearson, 2006）。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/增强病毒在蚊子中的感染和传播。这一知识可能有助于制定抗病毒策略。中心假设：病毒基因决定了CHIKV和中肠细胞表面蛋白的相互作用，从而促进伊蚊传播流行毒株LR2006 OPY1 2005。埃及伊蚊和伊蚊。蚊蚊子。目的1：确定并比较留尼旺岛流行毒株LR2006 OPY1和伊蚊中部非洲毒株SG41855的口服感染剂量50 （OID50）和感染动力学。埃及伊蚊和伊蚊。蚊蚊子。假设：目前印度洋暴发的CHIKV病毒的不同寻常的毒性和规模是由于病毒基因组的变化导致蚊子感染和传播增强。目的2：建立表达EGFP的感染性克隆，并建立一个复制子系统，以帮助确定伊蚊的CHIKV感染位点。埃及伊蚊和伊蚊。蚊蚊子。传染性克隆技术将为研究甲病毒与蚊子在分子水平上的相互作用提供重要工具。目的3：鉴定假想的Ae细胞表面受体蛋白。埃及伊蚊感染可调节基千伏病毒的蚊子传染性。假设：抑制伊蚊中chikv结合细胞表面蛋白的表达水平。埃及伊蚊导致感染和传播减少。创新、结果和益处：这项研究将从当前流行中提供急需的关于CHIKV的背景信息，并将使我们能够产生进一步研究蚊子-病毒相互作用机制所需的工具和方案。Fauci等人（2005）强调了与新发传染病有关的研究的重要性和价值，基孔肯雅病毒（CHIKV）是再次出现的病毒可能产生重大公共卫生影响的一个极好例子。正在流行的基孔肯雅热已在印度洋留尼汪岛（约占总人口的30%）造成25.5万多例人间病例，在印度造成10万多例。本研究将探索蚊子感染的机制，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态。

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.