Allergen-induced extracellular DNA in type 2 immunity

项目摘要/摘要 这个项目的长期目标是研究基本的免疫学机制。 参与哮喘和过敏性呼吸道疾病的发展。各种大气因素促成了 这些疾病的发病机制，包括病毒感染、过敏原暴露和空气污染。它是 越来越清楚的是，呼吸道上皮在协调免疫反应方面发挥着关键作用。 航空公司。尽管如此，参与启动和发展免疫反应的机制 环境因素还没有完全被理解。 免疫细胞对自身DNA的感知与各种器官的无菌炎症有关， 疾病病理生理学。我们最近发现，人类呼吸道上皮细胞迅速释放出 在体外过敏原暴露后，核DNA进入细胞外环境。Caspase-3被迅速激活 过敏原暴露在呼吸道上皮细胞中，没有明显的细胞凋亡或坏死迹象。自我- 在体内暴露于过敏原的幼稚小鼠，DNA也被释放到气道腔中，并被阻断 细胞外DNA(EDNA)抑制对过敏原的2型免疫反应。因此，我们假设 变应原诱导呼吸道上皮细胞快速释放自身DNA促进2型免疫 对空气传播的过敏原的反应。 本提案中描述的实验将通过关注两个基本问题来研究这一假设 问题。在目标1中，我们将确定呼吸道上皮细胞如何快速释放DNA以响应 体外过敏原暴露。我们将研究caspase-3和caspase-3非规范激活的机制。 分别启动和终止活跃的DNA释放。在目标2中，我们将确定如何 上皮源性EDNA在体内促进2型免疫和过敏性呼吸道炎症。我们会 研究晚期糖基化终产物模式识别受体(RAGE)在感觉中的作用 第二组先天淋巴样细胞和CD4+T细胞的效应功能被夸大。 我们将综合运用呼吸道细胞和分子生物学方面的互补专业知识。 奥格雷迪博士和奥格雷迪博士实验室中的上皮细胞、免疫学和2型免疫疾病模型 分别是Kita博士。为了这个项目，已经开发了新的和健壮的体外和体内模型。这些 研究将提供更好的了解呼吸道上皮如何对环境过敏原和 将定义在呼吸道中负责2型免疫反应的关键分子。最终，这些研究 将描述涉及变应原诱导的免疫反应的关键机制(S)，允许 治疗和理想预防免疫介导的呼吸道的新治疗靶点(S)的发现 疾病，如哮喘、慢性鼻窦炎和其他过敏性疾病。

PROJECT SUMMARY/ABSTRACT The long-term objective of this project is to investigate the fundamental immunological mechanisms involved in the development of asthma and allergic airway diseases. Various atmospheric factors contribute to the pathogenesis of these diseases, including viral infection, allergen exposure, and air pollution. It is becoming increasingly clear that the airway epithelium plays a key role in orchestrating immune responses in the airways. Nonetheless, the mechanisms involved in the initiation and development of immune responses to environmental factors are not fully understood. Sensing of self-DNA by immune cells has been implicated in sterile inflammation in various organs and the pathophysiology of diseases. We recently found that human airway epithelial cells rapidly release fragments of nuclear DNA into the extracellular milieu following allergen exposure in vitro. Caspase-3 was rapidly activated in airway epithelial cells upon allergen exposure without apparent signs of cellular apoptosis or necrosis. Self- DNA was also released into the airway lumen in naïve mice exposed to allergens in vivo, and blocking extracellular DNA (eDNA) suppressed type 2 immune responses to the allergens. Therefore, we hypothesize that allergen-induced rapid extracellular release of self-DNA by airway epithelial cells promotes type 2 immune responses to airborne allergens. The experiments described in this proposal will investigate this hypothesis by focusing on two fundamental questions. In Aim 1, we will determine how DNA is rapidly released by airway epithelial cells in response to allergen exposure in vitro. We will examine the mechanisms of non-canonical activation of caspase-3 and calpains, which initiate and terminate active DNA release, respectively. In Aim 2, we will determine how epithelium-derived eDNA promotes type 2 immunity and allergic airway inflammation in vivo. We will investigate the role of the pattern recognition receptor for advanced glycation endproducts (RAGE) in sensing eDNA and leading exaggerated effector functions of group 2 innate lymphoid cells and CD4+ T cells. We will employ a combination of complementary expertise in cellular and molecular biology of airway epithelial cells and immunology and disease models of type 2 immunity in the laboratories of Dr. O’Grady and Dr. Kita, respectively. Novel and robust in vitro and in vivo models have been developed for this project. These studies will provide a better understanding of how airway epithelium responds to environmental allergens and will define the key molecules responsible for type 2 immune responses in the airways. Ultimately, these studies will characterize the critical mechanism(s) involved in allergen-induced immune responses, allowing for the identification of novel therapeutic target(s) for treating and ideally preventing immune-mediated airway diseases, such as asthma, chronic rhinosinusitis, and other allergic disorders.