Immunobiology of Corneal Antigen-Presenting Cells

描述（由申请人提供）：项目摘要本提案的总体目标是为主要研究者（PI）提供成为独立研究人员所需的经验和技能，重点是研究免疫细胞运输机制。我的长期职业目标是建立一个全面而独立的研究项目，致力于剖析炎症和感染性角膜疾病中免疫细胞的运输机制，从而找到新的治疗靶点。角膜抗原呈递细胞（APC）在维持角膜的清晰度和保护视力方面具有关键作用。APC介导的免疫应答需要APC和T细胞之间的接触依赖性信息交换。成熟DC向幼稚T细胞递呈抗原可诱导T细胞活化并增殖为效应T细胞，而这又被认为是由多种机制控制的，包括调节性T细胞（Treg）的作用。APC的职业决策是APC和T细胞表面的调节分子。尽管APC在免疫系统中具有独特的地位，但APC进入角膜所需的信号以及它们离开角膜所需的线索仍然在很大程度上未被探索。在该项目的前期工作中，我们开发了一种新的多光子活体显微镜（MP-IVM）模型来研究麻醉小鼠完整角膜中的APC。这种成像方法使用转基因小鼠，其中APC亚群表达不同的遗传编码荧光标签，并以亚细胞分辨率产生APC的3D延时电影，与周围细胞相互作用。这些细胞将被研究，以调查引导它们到达正常和发炎角膜的交通信号，并将用于解决以下三个具体目标：1。剖析APC向正常和发炎角膜行进的分子机制; 2.）分析正常条件下和炎症状态下APC从角膜向局部淋巴结迁移的机制; 3）检测角膜移植后供体和宿主APC的空间、时间和行为特征及其与淋巴结T细胞的相互作用。这一目标还将分析效应T细胞或T细胞如何进入角膜。所提出的实验将产生一个全面的，机制导向的调查行为之间的相似性和不同的APC亚群在正常条件下和炎症。 公共卫生相关性：项目叙述：从拟议的研究中识别免疫细胞迁移到角膜和从角膜迁移的关键途径，将为炎症性、感染性和自身免疫性角膜疾病以及角膜移植的药物干预提供新的分子靶点。这些目标可能会导致新的和高度特异性的免疫治疗策略，通过调节免疫细胞的运输。

DESCRIPTION (provided by applicant): Project Summary The overall goal of this proposal is to provide the principal investigator (PI) with the experiences and skills necessary to become an independent researcher, with the focus on studying immune cell trafficking mechanisms. My long-term career goal is to establish a comprehensive and independent research program dedicated to dissect the trafficking mechanism of immune cells in inflammatory and infectious corneal disease, leading to new therapeutic targets. Corneal antigen-presenting cells (APC) have a critical role in maintaining the clarity of the cornea and preserving vision. APC-mediated immune responses require contact-dependent information exchange between APC and T cells. Ag presentation by mature DC to naive T cells induces T cell activation and proliferation into effector T cells, which is in turn thought to be controlled by several mechanisms, including the action of regulatory T cells (Treg). Career decisions taken by APC are regulated molecules on the surface of APC and T cells. Despite their unique position in the immune system, the signals APC need to enter the cornea, and the clues they require to leave the cornea, are still largely unexplored. In preliminary work for this project, we have developed a new multiphoton intravital microscopy (MP-IVM) model to study APC in intact corneas of anesthetized mice. This imaging approach uses transgenic mice, in which APC subsets expresses distinct genetically encoded fluorescent tags, and produces 3D time-lapse movies of APC at subcellular resolution, interacting with surrounding cells. These cells will be studied to investigate the traffic signals that guide them to normal and inflamed corneas and will be used to address the following three specific aims: 1.) To dissect the molecular mechanisms by which APC travel to normal and inflamed corneas; 2.) To analyze the mechanisms involved in migration of APC from the cornea to local lymph nodes under normal conditions and during inflammation; and 3) examine the spatial, temporal and behavioral characteristics of donor and host APC after corneal transplantation and their interaction with T cells in lymph nodes. This aim will also analyze how effector T cells or Tregs enter the cornea. The proposed experiments will generate a comprehensive, mechanism-oriented survey of the behavioral similarities and differences between distinct APC subsets under normal condition and inflammation. PUBLIC HEALTH RELEVANCE: Project Narrative: Identification of critical pathways of immune cell migration to and from the cornea from the proposed studies will provide new molecular targets for pharmacological intervention in inflammatory, infectious, and autoimmune corneal diseases, as well as in corneal transplantation. These targets may lead to novel and highly specific strategies for immunotherapy, through modulation of immune cell trafficking.