OCULAR SURFACE INJURY: INFLAMMATORY CASCADE AND HEALING OF CORNEAL WOUNDS

描述(申请人提供)：炎症反应及其消退是有效愈合角膜损伤所必需的。炎症发展为一系列顺序依赖的细胞迁移，而这种细胞迁移中准确的时间和分子关系是至关重要的。角膜中有一些其他血管床研究无法预测的独特特征，这种级联反应的失调降低了角膜伤口愈合的效率，或者积极地延迟了角膜伤口的愈合。研究设计：拟进行的研究仅限于一种动物模型：C57BL/6小鼠的角膜上皮磨损。小鼠模型为机械研究(例如转基因和基因敲除小鼠)提供了获得分子试剂和资源的途径。损伤是标准化的--切除没有或最小直接间质损伤的特定区域的上皮，在48小时的观察期内每隔6小时对炎症进行分析，确定细胞运输的动力学。具体目标涉及以前未被认识的角膜上皮损伤修复方面--具体地说，参与？/？T细胞和血小板促进愈合。目的1.明确中央角膜上皮磨损后，血小板在角膜缘血管和周边角膜基质中聚集的机制。假设：血小板的聚集依赖于与角膜缘血管中的白细胞的黏附，进而增加白细胞的聚集。我们发表的工作表明，循环中的血小板耗尽显著降低了角膜愈合。目标2.定义哪些机制？/？T细胞影响中央角膜上皮损伤后的炎症反应。假设：居民和移民？/？T细胞通过控制炎症过程，包括血小板的积累，是有效的上皮愈合所必需的。本申请中的初步数据显示？/？T细胞显著减少角膜愈合，并显著减少血小板和中性粒细胞在角膜缘的定位。角膜表面上皮细胞在维持角膜功能和最佳愈合过程中起着重要作用，关系到屈光手术的有效性和安全性以及角膜损伤的治疗。这项拟议的研究定义了角膜损伤引起的炎症促进或延缓愈合的机制，揭示了治疗干预的潜在靶点。

DESCRIPTION (provided by applicant): The inflammatory response and its resolution are necessary for efficient healing of corneal injuries. The inflammation develops as a cascade of sequentially dependent cellular emigrations, and the precise temporal and molecular relationships within this cellular trafficking are critical. There are unique features in the cornea not predictable from studies of other vascular beds, and dysregulation of this cascade diminishes the efficiency of or actively delays corneal wound healing. Research design: The proposed studies are limited to an animal model: corneal epithelial abrasion in C57BL/6 mice. A mouse model provides access to molecular reagents and resources for mechanistic studies (e.g., transgenic and knockout mice). The injury is standardized -- removal of a defined area of epithelium with no or minimal direct stromal injury, and analysis of inflammation at 6 hour intervals over an observation period of 48 hours defines the kinetics of cellular trafficking. The specific aims deal with previously unrecognized aspects of corneal epithelial wound repair -- specifically, the involvement of ?/? T cells and platelets in facilitating healing. Aim 1. Define mechanisms for the accumulation of platelets in limbal vessels and peripheral corneal stroma following central corneal epithelial abrasion. Hypothesis: Platelet accumulation depends on adhesion to leukocytes in limbal vessels and in turn augments leukocyte accumulation. Our published work shows that depletion of circulating platelets significantly reduces corneal healing. Aim 2. Define mechanisms by which ?/? T cells influence the inflammatory response to central corneal epithelial abrasion. Hypothesis: Resident and emigrated ?/? T cells are necessary for efficient epithelial healing through their control of the inflammatory process including the accumulation of platelets. Preliminary data in this application reveal that depletion of ?/? T cells significantly reduces corneal healing and significantly reduces platelet and neutrophil localization in the limbus. Epithelium on the surface of the cornea plays important roles in the maintenance of corneal function and optimal healing, a major concern for efficacy and safety of refractive surgical procedures and the treatment of corneal injury. The proposed research defines mechanisms by which inflammation in response to corneal injury promotes or retards healing, revealing potential targets for therapeutic intervention.