Evaluation of the Effects of Chikungunya N-linked Glycosylation on Pathogenesis

描述（由申请方提供）：甲病毒是人类发病和死亡的重要原因，这些病原体通过节肢动物传播，每年导致数千例衰弱性感染。基孔肯雅病毒（CHIKV）是重要的公共卫生问题;最近表征的遗传适应使该病毒能够有效地利用白纹伊蚊作为主要传播媒介，白纹伊蚊目前分布在世界各地[1，2]。因此，近年来CHIKV的流行性传播已导致非洲、印度洋岛屿、印度和东南亚的数百万人感染[3-9]，以及人类病例输入到美国、加勒比海和欧洲[8]。在某些情况下，这之后是局部传输周期[10]。传统的病媒控制一直是对抗蚊媒病毒的主要策略;然而，蚊子病媒的种群扩张，加上缺乏疫苗，强调了开发替代抗病毒治疗靶点的必要性。然而，CHIKV和介导清除和发病机制的脊椎动物先天免疫应答之间的相互作用仍然不清楚。这项研究的长期目标是使用反向遗传学和炎症性关节炎的小动物模型来识别驱动甲病毒诱导疾病的病毒和宿主因素。本申请的目的是鉴定CHIKV包膜聚糖与宿主C型凝集素受体之间的特异性相互作用，并阐明这些相互作用对先天免疫细胞嗜性、信号传导和功能的影响。具体目的1：分析CHIKV N-连接聚糖在体内和体外调节CHIKV感染和炎症基因诱导中的作用。具体目的2：鉴定与CHIKV相互作用的特异性C型凝集素受体 包膜/病毒体N-连接聚糖。我们假设CHIKV的发病机制是免疫介导的，并且是通过病毒N-连接聚糖和宿主C-型凝集素之间的相互作用刺激先天免疫激活的结果。已经设计了实验以鉴定一组已知聚糖缺陷的CHIKV与宿主C型凝集素的表达文库之间的特异性相互作用。此外，将在体外和体内评价这些病毒，以表征CHIKV聚糖对炎症、发病机制和先天免疫激活和细胞因子产生的影响。所提出的研究对于CHIKV抗病毒治疗剂的开发具有高度意义，因为它们将直接评估刺激保护性和致病性应答的病毒和宿主因子之间的相互作用，因此可以鉴定新的治疗靶点。

DESCRIPTION (provided by applicant): Alphaviruses are a significant cause of human morbidity and mortality with arthropod-borne transmission of these agents resulting in thousands of debilitating infections per annum. Chikungunya virus (CHIKV) is significant public health concern; recently characterized genetic adaptation has allowed this virus to efficiently utilize Aedes albopictus mosquitoes, which are now distributed worldwide, as a primary transmission vector [1,2]. As such, in recent years epidemic transmission of CHIKV has resulted in millions of human infections in Africa, the Indian Ocean islands, India, and Southeast Asia [3-9] as well as the importation of human cases into the United States, the Caribbean, and Europe [8]. In some instances this has been followed by localized transmission cycles [10]. Classical vector control has been the primary strategy to combat mosquito-borne viruses; however, population expansion of mosquito vectors, coupled with a lack of vaccines serves to emphasize the need for the development of alternate anti-viral therapeutic targets. However, interactions between CHIKV and the vertebrate innate immune response that mediate clearance and pathogenesis remain poorly defined. The long-term goal of this research is to use reverse genetics and small animal models of inflammatory arthritis to identify viral and host factors that drive alphavirus-induced disease. The objective of this application is to identify specific interactions between CHIKV envelope glycans and host C-type lectin receptors and elucidate the consequence of those interactions on innate immune cell tropism, signaling, and function. Toward this goal the following specific aims are proposed: Specific Aim 1: To analyze the role of CHIKV N-linked glycans in modulating CHIKV infection and inflammatory gene induction in vivo and in vitro. Specific Aim 2: To identify specific C-type lectin receptors that interact with CHIKV envelope/virion N-linked glycans. We hypothesize that CHIKV pathogenesis is immune mediated and results from stimulation of innate immune activation via interactions between viral N-linked glycans and host C-type lectins. Experiments have been designed to identify specific interactions between a panel of CHIKV deficient for known glycans and an expression library of host C-type lectins. Additionally, these viruses will be evaluated in vitro and in vivo toward characterizing the effects of CHIKV glycans on inflammation, pathogenesis, and innate immune activation and cytokine production. The proposed studies are highly significant to the development of CHIKV anti-viral therapeutics as they will directly assess the interactions between viral and host factors that stimulate protective and pathogenic responses and as such may identify novel therapeutic targets.