Identification and Characterization of Entry Factors Critical for Rift Valley Fever Virus Infection and Pathogenesis

项目总结/摘要 裂谷热病毒（RVFV）是一种静脉病毒，属于Phenuiviridae（原布尼亚病毒科）家庭 负义RNA病毒。RVFV作为一种新兴的蚊媒病毒，其重要性日益凸显 通过将其指定为NIAID A类病原体并将其纳入世界卫生组织优先疾病蓝图。 最近，流行病防范创新联盟（CEPI）也将RVFV作为其 新兴传染病疫苗计划，进一步强调RVFV对全球的潜在影响 健康和经济。虽然RVFV在整个撒哈拉以南非洲流行， 在北美洲发现了RVFV，这突出表明RVFV在非流行国家出现的可能性， 包括美国在内在暴发期间，RVFV在包括绵羊和绵羊在内的牲畜中引起严重疾病， 牛，这极大地影响了资源有限环境中的社会经济框架。人类是溢出- 感染可导致严重后果，包括肝坏死，出血热， 脑炎和视网膜血管炎。尽管其对人类健康的重要性和潜在的负面影响 在病毒流行的资源有限国家的社会经济结构中， 有效的预防性和治疗性治疗选择。这一差距部分是由于我们缺乏知识， 导致RVFV感染的宿主因素。为了满足这一需求，我们进行了基因组筛选， 几个关键因素，包括一个潜在的进入因素，我们将通过多学科的特点， approach.在支持，我们提供了令人信服的初步数据，包括在体外验证宿主因子足够 和缺陷细胞，反式互补研究，RVFV糖蛋白Gn和宿主之间的直接相互作用 蛋白质的体外研究，内源性配体对来自 进化上不同的宿主，以及在两种条件敲除中保护RVFV感染的初步结果 小鼠模型。重要的是，我们已经产生了许多关键试剂，包括大多数细胞系和蛋白质， 和支持可行性的基因敲除小鼠。重要的是，这项工作将由高生产力和 在拟议研究的各个方面具有专业知识的合作研究者，包括生物化学、RVFV 发病机理、免疫学、蛋白质组学、结构生物学和病毒学。完成拟议的研究将 定义具有组织特异性相关性的靶细胞中RVFV的新型宿主或进入因子。作为一种特殊的受体 对于RVFV以前没有被确定，这些研究将为设计提供重要信息， 预防RVFV感染和疾病的治疗干预。在完成时，我们希望填补一个关键的空白， 并为治疗开发提供新的靶点。

Project Summary/Abstract Rift Valley fever virus (RVFV) is a phlebovirus that belongs to the Phenuiviridae (formerly Bunyaviridae) family of negative-sense RNA viruses. As an emerging mosquito-borne virus, the significance of RVFV is highlighted by its designation as a NIAID Category A pathogen and its inclusion on the WHO's Blueprint of Priority Diseases. Recently, the Coalition for Epidemic Preparedness Innovations (CEPI) has also included RVFV as a part of their emerging infectious diseases vaccine program, further emphasizing the potential impact of RVFV on the global health and economy. While RVFV is endemic throughout sub-Saharan Africa, competent mosquito vector species are found in North America, highlighting the potential for emergence of RVFV in non-endemic countries, including the United States. During outbreaks, RVFV causes severe disease in livestock, including sheep and cattle, which dramatically impact the socioeconomic framework in resource limited settings. Humans are spill- over hosts, where infections can result in severe consequences, including hepatic necrosis, hemorrhagic fever, encephalitis, and retinal vasculitis. Despite its significance to human health and the potential to negatively impact the socioeconomic fabric of resource-limited countries where the virus is endemic, there is a lack of safe and efficacious prophylactic and therapeutic treatment options. This gap is in part due to our lack of knowledge on host factors that contribute to RVFV infection. To address this need, we conducted a genomic screen that defined several critical factors, including a potential entry factor, which we will characterize by a multidisciplinary approach. In support, we provide compelling preliminary data, including in vitro validation in host factor sufficient and deficient cells, transcomplementation studies, direct interaction between RVFV glycoprotein Gn and the host proteins in vitro, inhibition of the entry factor by endogenous ligands in vitro in multiple cell lines from evolutionarily distinct hosts, and preliminary results of protection from RVFV infection in two conditional knock out mouse models. Importantly, we have generated many key reagents, including most cell lines and proteins, and knock-out mice supporting the feasibility. Importantly, this work will be performed by highly productive and collaborative investigators with expertise in every aspect of the proposed studies, including biochemistry, RVFV pathogenesis, immunology, proteomics, structural biology, and virology. Completion of the proposed studies will define novel host or entry factors for RVFV in target cells with tissue-specific relevance. As a specific receptor for RVFV has not previously been identified, these studies will provide important information for design of therapeutic interventions to prevent RVFV infection and disease. At the completion, we expect to fill a key gap in the field and to provide novel targets for therapeutic development.