TONSILS: AN UNRECOGNIZED ROLE IN INFLUENZA VIRUS EVOLUTION

确定导致流感病毒（IV）致病的宿主因子对于疾病控制和预防至关重要 流行病扁桃体包括位于哺乳动物的鼻咽和鸟类的盲肠中的2个淋巴器官， 哪种静脉注射是肠内的扁桃体是各种病毒感染和传播的起始部位，但它们在IV 发病机制尚不清楚。我提出的研究将为扁桃体如何促进IV发病机制提供新的见解， 免疫反应和适应，通过确定扁桃体在IV发病机制中的作用， 雪貂，以概括人类亚群对IV感染严重程度和疫苗接种的异质性反应 有/无扁桃体，并探讨扁桃体在IV适应中的作用。我最近的研究表明， 扁桃体上皮细胞（HTEC）易受IV感染，在体外有效复制不同的IV亚型。 我将在这些发现的基础上，通过对静脉感染的动态和分布进行时间密集型监测， 雪貂的扁桃体我收集并分析了美国过去60年来的人类扁桃体切除术数据，发现 在不同年龄组中，扁桃体切除术的人类亚群的百分比很高。患病率，疾病严重程度， 这些亚群中IV感染的免疫力和水平尚不清楚，扁桃体在流行病或 IV的大流行传播尚未确定。我以前发现，HTECs诱导趋化因子和细胞因子的释放， 感染先前的临床研究报告对IV减毒活疫苗的唾液IgA免疫应答没有差异 在扁桃体切除术前后的个体中，但这些研究受到患者数量少的限制，并受到以下因素的混淆： 抗原原罪我将使用雪貂，以确定扁桃体切除术如何影响免疫力造成的IV感染， 疫苗我将测量感染和/或免疫后抗体应答的数量和质量，并比较T- 细胞和B细胞的活动与无扁桃体的雪貂。软腭是IV适应的重要部位， 在口腔中向下并经过扁桃体的前后。扁桃体组织中静脉的复制适合度 可能诱导快速选择，表面上防止感染并降低其大流行的可能性。因此，我建议 验证扁桃体在IV适应中的作用，该组织通常不在IV动物模型中取样，并研究 不同的人类IV病毒在扁桃体中的复制。获得突变和转换受体结合特异性之间 鸟类和人类的唾液酸（SA）偏好是IV传播和适应的关键。我以前发现， 鸟类扁桃体上皮细胞富含人α 2，6和鸟类α 2，3连接的SA受体并支持IV复制。 我将使用改变SA偏好的基因工程IV进行传播研究并分析病毒 扁桃体内的适应性可能比软腭更快地通过使用功能丧失来选择可传播的IV approach.该提案的指导阶段将在圣裘德儿童研究医院进行，由以下机构主持： Richard Webby将阐明扁桃体在IV发病机制和感染免疫反应中的作用。的 独立阶段将侧重于对IV疫苗的免疫应答和IV适应。机构资源，学术 我的建议中概述的环境和教育机会将确保我成功地过渡到独立。

Identifying the host factors that contribute to influenza virus (IV) pathogenesis are critical for disease control and preventing pandemics. The tonsils comprise 2 lymphoid organs located in the nasopharynx of mammals and in the cecum of birds, in which IVs are enteric. The tonsils are an initial site of various viral infections and transmission, but their role in IV pathogenesis is unclear. My proposed studies will provide new insights on how the tonsils contribute to IV pathogenesis, immune responses, and adaptation by identifying the role of the tonsils in IV pathogenesis, performing tonsillectomy in ferrets to recapitulate the heterogeneous responses to IV infection severity and vaccination in subpopulations of humans with/without tonsils, and exploring the role of the tonsils in IV adaptation. My recent study demonstrated that human tonsillar epithelial cells (HTECs) are susceptible to IV infections, with effective replication of different IV subtypes in vitro. I will expand upon these findings by performing time-intensive monitoring of IV infection dynamics and distribution in the tonsils of ferrets. I collected and analyzed human tonsillectomy data over the last 60 years in the US and found that the percentage of human subpopulations with tonsillectomies is high in different age groups. The prevalence, disease severity, and level of immunity of IV infections in these subpopulations are unknown, and the role of the tonsils in epidemic or pandemic spread of IVs is undetermined. I previously found that HTECs induce chemokine and cytokine release during IV infection. Previous clinical studies reported no differences in salivary IgA immune responses to IV live attenuated vaccine in individuals before and after tonsillectomy, but these studies were limited by low patient numbers and confounded by original antigenic sin. I will use ferrets to ascertain how tonsillectomy affects immunity resulting from the IV infection and vaccine. I will measure the quantity and quality of antibody responses after infection and/or immunization and compare T- cell and B-cell activity in ferrets with and without tonsils. The soft palate is an important site of IV adaptation, extending downward in the oral cavity and passing anterior and posterior to the tonsils. The replicative fitness of IVs in tonsillar tissues may induce rapid selection, ostensibly preventing infection and reducing their pandemic potential. Therefore, I propose to verify the role of the tonsils in IV adaptation a tissue not typically sampled in animal models of IV and investigate the extent of different human IV replication in the tonsils. Acquiring mutations and switching receptor-binding specificity between avian and human sialic acid (SA) preferences are key for IV transmission and adaptation. I previously found that both human and avian tonsil epithelial cells are rich in both human α2,6 and avian α2,3–linked SA receptors and support IV replication. I will use genetically engineered IVs with altered SA preferences to conduct transmission studies and analyze the viral fitness within the tonsils that may select for transmissible IVs more rapidly than the soft palate by using a loss-of-function approach. The mentored phase of this proposal will occur at St. Jude Children Research Hospital under the auspices of Richard Webby and will elucidate the role of the tonsils in IV pathogenesis and immune responses to infection. The independent phase will focus on immune responses to IV vaccines and IV adaptation. The institutional resources, academic environment, and educational opportunities outlined in my proposal will ensure my successful transition to independence.