Contribution of Mast Cells in non-allergic ocular inflammation

肥大细胞在非过敏性眼部炎症中的作用

• 批准号: 10044804
• 负责人: Sunil K Chauhan
• 金额: $ 24.88万
• 依托单位: SCHEPENS EYE RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2023-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10044804
• 关键词: Adrenal Cortex Hormones; Adverse effects; Age related macular degeneration; Allergic Disease; Anti-Inflammatory Agents; Architecture; Autoimmunity; Biological Assay; Blindness; Blood Circulation; CXCL2 gene; Cell physiology; Chemotactic Factors; Chemotaxis; Cornea; Corneal Injury; Data; Disease; Effector Cell; Elements; Epithelial Cells; Eye; Eye Injuries; Fibroblasts; Foundations; Goals; Graft Rejection; HMGB1 gene; High Prevalence; Hour; IgE; Immune; Immunology procedure; Immunosuppressive Agents; Impaired wound healing; In Vitro; Infection; Infiltration; Inflammation; Inflammation Mediators; Inflammatory; Injury; Innate Immune Response; Interleukin-1 beta; Keratoplasty; Knockout Mice; Laboratories; Light; Malignant Neoplasms; Mediating; Mediator of activation protein; Molecular; Mus; Necrosis; Neutrophil Activation; Neutrophil Infiltration; Neutrophilic Infiltrate; Pathogenicity; Pathology; Pharmaceutical Preparations; Phase; Play; Publications; Publishing; Reporting; Research; Role; Sentinel; Series; Site; Sterility; Testing; Therapeutic; Tissues; Treatment Efficacy; Tryptase; Visual impairment; Wound Infection; allergic response; base; beta-n-acetylhexosaminidase; chemokine; corneal epithelium; cytokine; design; differential expression; experimental study; immune activation; immune function; in vivo; injured; interest; macrophage; mast cell; migration; mouse model; neutrophil; novel; novel therapeutic intervention; novel therapeutics; prevent; receptor; reconstitution; recruit; repository; response; sensor; side effect; tissue injury; tissue repair; translational impact

Ocular injury is a leading cause of corneal blindness, resulting in millions of cases of visual impairment globally each year. Currently, the uncontrolled immune activation and tissue damage that occur following ocular injury are treated with non-specific anti-inflammatory drugs (e.g. corticosteroids), which are rife with deleterious side effects such as delayed wound healing and infection. Our research aims to identify the specific cellular and molecular factors that mediate early immune cell activation and infiltration following ocular injury, so that novel therapeutics may be developed. Our group’s recently published reports and preliminary data have identified tissue-resident mast cells as the primary reservoir of neutrophil-chemoattractants at the cornea, and have established that instant release of preformed CXCL2 by mast cells is critical for early neutrophil migration (<1 hour) following injury. Early-recruited ‘scout’ neutrophils subsequently release chemoattractant factors that drive a robust second phase of neutrophil infiltration, amplifying the innate immune response. Excessive recruitment and activation of neutrophils is known to cause deleterious inflammation and damage corneal architecture. These observations pose a critical question: How do mast cells sense tissue injury and promote early neutrophil recruitment? Our data show that damaged corneal epithelial cells (but not resident stromal fibroblasts or macrophages) release inflammatory mediators that activate mast cells. In accordance with our laboratory’s expertise in immunological assays and utilizing a well-characterized murine model of sterile corneal stromal injury, we propose a series of novel experiments to decipher the role of mast cells as sensors of tissue injury. In Aim 1, we will test the hypothesis that danger-associated inflammatory molecules IL33, IL36γ and HMGB1 released from corneal epithelial cells activate mast cells in an IgE- independent manner. Specifically, we will (i) establish that necrotic epithelial cells stimulate mast cells relative to healthy and IL1β-treated epithelial cells using mast cell-specific tryptase and β-hexosaminidase release assays; and (ii) identify the key danger-associated molecules expressed by corneal epithelial cells that activate mast cells. In Aim 2, we will test the hypothesis that in vivo blockade of IL36γ function will be more effective, relative to IL33 and HMGB1, in suppressing mast cell activation, resulting in reduced neutrophil infiltration and tissue damage. Specifically, we will determine the effect of (i) silencing select mast cell- activating mediators, and (ii) silencing receptors for select mediators on mast cells, on mast cell activation and early neutrophil recruitment during corneal injury. We will also evaluate the therapeutic potential of local blockade of select mediators. It is anticipated that this research will have significant translational impact due to the high prevalence of ocular injury and inflammatory disease, as well as the relevance of mechanisms governing neutrophil infiltration to non-ocular tissues.

眼损伤是角膜失明的主要原因，导致全球数百万例视力障碍 每年。目前，眼损伤后发生的不受控制的免疫激活和组织损伤 使用非特异性抗炎药物（例如皮质类固醇）治疗，这些药物充满有害的一面 诸如伤口愈合延迟和感染等影响。我们的研究旨在确定特定的细胞和 介导眼损伤后早期免疫细胞激活和浸润的分子因素，因此新的 可能会开发治疗方法。 我们小组最近发表的报告和初步数据已经确定了组织驻留肥大 细胞作为角膜中性粒细胞化学引诱剂的主要储存库，并已确定 肥大细胞立即释放预先形成的 CXCL2 对于早期中性粒细胞迁移（<1 小时）至关重要 受伤。早期招募的“侦察”中性粒细胞随后释放趋化因子，驱动强大的 中性粒细胞浸润的第二阶段，放大先天免疫反应。过度招聘和 众所周知，中性粒细胞的激活会引起有害的炎症并损害角膜结构。 这些观察结果提出了一个关键问题：肥大细胞如何感知组织损伤并促进 早期中性粒细胞募集？我们的数据显示，受损的角膜上皮细胞（但不是常驻基质细胞） 成纤维细胞或巨噬细胞）释放激活肥大细胞的炎症介质。按照我们的 实验室在免疫测定方面的专业知识和利用良好表征的无菌小鼠模型 角膜基质损伤，我们提出了一系列新颖的实验来破译肥大细胞的作用 组织损伤的传感器。在目标 1 中，我们将检验以下假设：与危险相关的炎症 角膜上皮细胞释放的分子 IL33、IL36γ 和 HMGB1 激活 IgE 中的肥大细胞 独立的方式。具体来说，我们将 (i) 确定坏死的上皮细胞刺激肥大细胞 使用肥大细胞特异性类胰蛋白酶和 β-己糖胺酶相对于健康和 IL1β 处理的上皮细胞 释放测定； (ii) 识别角膜上皮细胞表达的关键危险相关分子 激活肥大细胞。在目标 2 中，我们将测试体内阻断 IL36γ 功能的假设 相对于 IL33 和 HMGB1，在抑制肥大细胞活化方面更有效，导致中性粒细胞减少 浸润和组织损伤。具体来说，我们将确定（i）沉默选择的肥大细胞的效果- 肥大细胞激活介质，以及 (ii) 肥大细胞上选择介质的沉默受体 以及角膜损伤期间早期中性粒细胞的募集。我们还将评估当地的治疗潜力 封锁选定的调解员。预计这项研究将产生重大的转化影响 由于眼损伤和炎症性疾病的高发病率以及机制的相关性 控制中性粒细胞浸润至非眼组织。