Rotavirus interaction with gut intraepithelial lymphocytes

项目摘要 小肠上皮细胞（IEC）是抵抗人类肠道病毒的第一道防线， 是婴幼儿腹泻和死亡的最常见和主要原因。IEC如何 与小肠中的上皮内淋巴细胞（IEL）沟通并协调抗病毒反应 被严重低估了我们的总体目标是更好地定义宿主免疫信号通路， 并利用这些信息来制定治疗干预措施， 减轻腹泻和后遗症。 我们的初步结果与我们的预期相反，并表明两个IEL子集的数量 在体内早期轮状病毒感染期间显著降低。我们还发现轮状病毒感染改变了 几种促炎趋化因子在感染的人和小鼠IEC中的表达。基于这些数据 和以前的出版物，我们假设IEL是宿主防御的重要介质， 轮状病毒感染和轮状病毒编码的因子拮抗IEL的抗病毒活性 宿主小肠通过抑制趋化因子表达。 目前，由于缺乏合适的模型系统，这些假设的检验受到阻碍。因此我们 已经开发了一种高度易处理的鼠轮状病毒反向遗传学方法， 小鼠模型，以及几种创新的原代人和鼠小肠类器官培养系统， 这将提供一个前所未有的解决方案的理解IEC-IEL串扰的背景下，肠 病毒感染 在目标1中，我们将使用免疫学方法确定IEL在体内轮状病毒感染中的功能性抗病毒作用， 方法和基因敲除小鼠。在目标2中，我们将确定病毒因子 抑制感染的IEC中的趋化因子表达。总的来说，我们希望这些研究能够建立一个新的 粘膜抗病毒免疫的范例，特别是在生命早期，当大多数肠道感染发生时。我们也 期望确定新的轮状病毒免疫逃避策略，这将为开发宿主- 基于广谱抗病毒疗法和下一代候选疫苗。

Project Summary Small bowel intestinal epithelial cells (IECs) are the first line of defense against human enteric viruses, the most common and leading causes of diarrhea and death in infants and young children. How IECs communicate with intraepithelial lymphocytes (IELs) in the small intestine and orchestrate antiviral responses is heavily understudied. Our overall objectives are to better define the host immune signaling pathways in the gastrointestinal tract during infections and to use that information to develop therapeutic interventions to alleviate diarrhea and sequelae. Our preliminary results contrasted our expectation and demonstrated that the numbers of two IEL subsets are significantly reduced during early rotavirus infection in vivo. We also found that rotavirus infection alters the expression of several pro-inflammatory chemokines in infected human and mouse IECs. Based on these data and prior publications, we hypothesize that the IELs are important mediators of host defense against rotavirus infection and that rotavirus-encoded factors antagonize the antiviral activity of IELs in the host small intestine via inhibition of chemokine expression. Testing these hypotheses is currently hampered by the lack of suitable model systems. Accordingly, we have developed a highly tractable murine rotavirus reverse genetics method, a pathologically relevant neonatal mouse model, and several innovative primary human and murine small bowel organoid culturing systems, which will provide an unprecedented resolution of understanding of IEC-IEL crosstalk in the context of enteric viral infections. In Aim 1, we will define a functional antiviral role of IELs in rotavirus infection in vivo using immunological approaches and gene knockout mice. In Aim 2, we will identify the potential mechanism by which viral factors dampen chemokine expression in infected IECs. Collectively, we expect these studies to establish a new paradigm of mucosal antiviral immunity, especially early in life when most enteric infections occur. We also expect to identify novel rotavirus immune evasion strategies, which will inform new strategies to develop host- based broad-spectrum antiviral therapeutics and next-generation vaccine candidates.