Mechanisms of Neuronal Infection by Prototype Emerging Bunyaviruses

项目总结/摘要 布尼亚病毒是一组具有全球卫生相关性的动物和人类病原体。布尼亚病毒目 顺序包括尽管序列不同但基因组和蛋白质结构相似的病毒家族。 这些媒介传播病毒的共同点是能够引起中枢神经系统（CNS）疾病， 并发症和偶尔死亡。缺乏对大脑中关键靶细胞的定义及其影响 病毒感染对大脑微环境的影响是我们对布尼亚病毒认识的主要限制 这也限制了我们制定对策的能力。目标的后果 细胞感染是未知的，神经系统疾病的病毒决定因素还没有被描述。克服 鉴于这一局限性，我们提出了一个比较分析的神经发病机制的3个医学上重要的原型 新出现的布尼亚病毒，并确定了相关神经元细胞中感染和发病机制的贡献者。La 克罗斯病毒（LACV）发现于北美，是儿童病毒性脑炎的主要原因， 美国的裂谷热病毒（RVFV）是世卫组织的一种优先疾病，可引起出血热暴发 和脑炎。奥罗波什病毒（Oropouche virus，ORFV），在南美洲发现， 30多场大规模流行病导致超过50万人感染发热性疾病。由于缺乏直接比较， 在我们对布尼亚病毒神经发病机制的理解方面， 机制等本提案将提供所有3种病毒在CNS细胞嗜性方面的比较分析， 先天性免疫应答和细胞死亡途径。我们最近 已发表的数据表明，宿主细胞蛋白LDL受体相关蛋白1（Lrp 1）对于有效的 细胞感染RVFV和Oleus。Lrp 1在LACV感染中作用的初步数据进一步支持了 相似的趋向性。我们假设这些神经毒性病毒共享重叠的靶点， 由宿主细胞蛋白Lrp 1介导的CNS中的细胞。病毒的非结构蛋白，由小的 基因组片段（NS）是宿主细胞抗病毒反应的主要拮抗剂和关键调节剂 在感染期间。我们进一步假设每种病毒的神经毒力程度与NS蛋白有关 功能我们高度协作和协同的团队由艾米·哈特曼博士（PI）领导，她是 RVFV的发病机理和Gaya Amarasinghe博士（Co-I），一位在宿主-病原体方面具有专长的生物化学家 交互.另外两个Co-I的是伦纳德D 'Aiuto博士和扎卡里威尔斯博士，是病毒感染的专家， 人类神经元和啮齿动物神经生物学。本R 01提案代表了多学科 方法来推进我们对布尼亚病毒与神经元相互作用的理解。

PROJECT SUMMARY/ABSTRACT Bunyaviruses are a diverse group of animal and human pathogens of global health relevance. Bunyavirales order encompasses viral families with similar genome and protein organization despite divergent sequences. Common to these vector-borne viruses is the ability to cause central nervous system (CNS) disease with concomitant morbidity and occasional mortality. Lack of definition of key target cells in the brain and the effect of virus infection on the brain microenvironment are major limitations in our knowledge of bunyavirus neuropathogenesis that has also limited our ability to develop countermeasures. The consequences of target cell infection are unknown, and viral determinants of neurologic disease have not been delineated. To overcome this limitation, we propose a comparative analysis of the neuropathogenesis of 3 medically important prototype emerging bunyaviruses and define contributors to infection and pathogenesis in relevant neuronal cells. La Crosse virus (LACV) is found in North America and is the primary cause of pediatric viral encephalitis in the United States. Rift Valley Fever virus (RVFV), a WHO Priority Disease, causes outbreaks of hemorrhagic fever and encephalitis throughout Africa. Oropouche virus (OROV), is found in South America and has caused more than 30 large epidemics resulting in over 500,000 human cases of febrile illness. Due lack of direct comparisons, substantial gaps remain in our understanding of bunyavirus neuropathogenesis, including molecular mechanisms. This proposal will provide comparative analysis of all 3 viruses with regards to CNS cell tropism, innate immune responses, and cell death pathways using novel in vitro and ex vivo model systems. Our recently published data shows that the host cell protein LDL-receptor related protein 1 (Lrp1) is important for efficient cellular infection by RVFV and OROV. Preliminary data on the role of Lrp1 in LACV infection further supports similar tropisms by divergent viruses. We hypothesize that these neurovirulent viruses share overlapping target cells in the CNS mediated by the host cell protein Lrp1. Viral non-structural protein produced from the small genome segment (NSs) functions as the main antagonist of host cell antiviral responses and a key modulator during infection. We further hypothesize that the degree of neurovirulence of each virus is related to NSs protein function. Our highly collaborative and synergistic team is led by Dr. Amy Hartman (PI), an expert in the pathogenesis of RVFV and Dr. Gaya Amarasinghe (Co-I), a biochemist with expertise in host-pathogen interactions. Two additional Co-I’s are Dr. Leonard D’Aiuto and Dr. Zachary Wills, are experts in viral infection of human neurons and rodent neurobiology, respectively. This R01 proposal represents a multidisciplinary approach to advance our understanding of bunyavirus interactions with neurons.