Mechanisms of Neuronal Infection by Prototype Emerging Bunyaviruses

项目摘要/摘要 布尼亚病毒是一组与全球健康相关的动物和人类病原体。布尼亚维拉莱斯 目包括基因组和蛋白质组织相似的病毒家族，尽管序列不同。 这些媒介传播的病毒的共同之处是能够引起中枢神经系统(CNS)疾病 随之而来的发病率和偶尔的死亡率。缺乏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本亚病毒认识的主要限制 神经发病机制也限制了我们制定对策的能力。目标的后果 细胞感染尚不清楚，神经系统疾病的病毒决定因素也尚未确定。要克服 这一局限，我们提出了3个医学上重要的原型的神经发病机制的比较分析 新出现的布尼亚病毒，并确定相关神经细胞中感染和致病的贡献者。拉 Crosse病毒(LACV)在北美被发现，是儿童病毒性脑炎的主要原因 美国。裂谷热病毒(RVFV)是世卫组织的优先疾病，导致出血热暴发 以及整个非洲的脑炎。奥罗波什病毒(Oropouche Virus，OROV)在南美洲被发现，并已引起更多 30多次大规模疫情导致50多万人患上发热病。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上仍然存在很大差距，包括分子 机械装置。这项建议将提供关于中枢神经系统细胞嗜性的所有3种病毒的比较分析， 使用新的体外和体外模型系统的先天免疫反应和细胞死亡途径。我们最近 已发表的数据显示，宿主细胞蛋白低密度脂蛋白受体相关蛋白1(LRP1)对于高效 RVFV和Orov的细胞感染。LRP1在LACV感染中作用的初步数据进一步支持 不同的病毒也有相似的趋向性。我们假设这些神经毒性病毒有重叠的靶点。 中枢神经系统中的细胞由宿主细胞蛋白LRP1介导。由小分子产生的病毒非结构蛋白 基因组片段(NSS)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NSS蛋白有关 功能。我们高度协作和协同的团队由艾米·哈特曼(PI)博士领导，他是 RVFV的发病机制和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 互动。另外两位Co-I是Leonard D‘Aiuto博士和Zachary Wills博士，他们是病毒感染的专家 人类神经元和啮齿动物神经生物学。这份R01提案代表了一个多学科 提高我们对布尼亚病毒与神经元相互作用的理解的方法。

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.