A novel ex vivo model of West Nile virus infection in human lymphoid tissue

描述(申请人提供)：西尼罗河病毒(WNV)是一种高度毒性的人类中枢神经系统(CNS)病原体，也是美国流行性脑炎的最常见原因。由于目前还没有针对西尼罗河病毒的疫苗或特定的抗病毒治疗方法，因此了解其发病机制是当务之急。感染后，西尼罗河病毒被运送到当地的引流淋巴结，在那里触发病毒的初级放大和关键的宿主防御反应；然而，人们对在人类这一交界处发生的事件知之甚少。为了研究这一点，我们建立了一个WNV感染的体外人类淋巴组织模型。在初步研究中，我们表明，西尼罗河病毒在所有接受测试的捐赠者中复制旺盛，并且可以检测到西尼罗河病毒感染的细胞。在这项应用中，我们将使用两种在人类中具有不同致病潜力的西尼罗河病毒株来表征对西尼罗河病毒感染的细胞反应，并确定淋巴组织内允许的靶细胞(目标1)，测量感染期间的炎症反应(目标2)，并确定淋巴内病毒优先复制的解剖环境(目标3)。了解人类系统中的这些病毒和细胞方面，以及神经侵袭性和非神经侵袭性WNV毒株之间的差异，不仅将提供对早期感染事件的第一次窥探，而且还将导致关于人类体内易感性的新假设。

DESCRIPTION (provided by applicant): West Nile virus (WNV) is a highly virulent human pathogen of the central nervous system (CNS) and the most common cause of epidemic encephalitis in the United States. Since there are no vaccines or specific antiviral treatments available for WNV, understanding its pathogenesis is a high priority. Following infection, WNV is transported to the local draining lymph nodes, where primary amplification of the virus and key host defense responses are triggered; however, there is very little known about the events that take place at this junction in humans. To study this, we developed an ex vivo human lymphoid tissue model of WNV infection. In preliminary studies, we show that WNV replicates robustly in all donors tested, and WNV-infected cells can be detected. In this application, we will use two strains of WNV that differ in their pathogenic potential in humans to characterize the cellular response to WNV infection and identify the permissive target cells within the lymphoid tissue (Aim 1), measure the inflammatory response during the infection (Aim 2), and determine the anatomical environment within the lymph node where virus replication preferentially occurs (Aim 3). Understanding these viral and cellular aspects in a human system and how these differ between a neuroinvasive and non-neuroinvasive strain of WNV will not only provide the first glimpse into early infection events, but also lead to new hypotheses for in vivo susceptibility in humans.