ROLE OF EPITHELIUM IN AIRWAY IMMUNITY

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目和 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 人们对人类婴儿肺部的先行事件知之甚少，这些事件容易在以后的生活中对吸入的过敏原产生病理性免疫反应。我们不知道婴儿肺部的结构细胞是否可以显着影响对吸入环境挑战的免疫反应表型。特别重要的是传导气道的上皮细胞，它在结构和功能上都准备好充当适应性免疫系统的联络人。该提案的主要目的是确定婴儿肺部的传导气道上皮如何影响对吸入过敏原的适应性免疫反应。我们的总体假设是，婴儿肺上皮细胞通过组成型 CCL20 趋化因子表达促进气道趋化因子受体 CCR6 T 淋巴细胞的募集，在哮喘表型的起始中发挥核心作用。这一假设基于从气道上皮细胞培养物中获得的初步数据，证明了 CCL20 通过 IL-17A 的年龄依赖性表达和抑制性 microRNA 调节。我们还在暴露于过敏原的幼猴的气道中发现了一群产生 IL-17A 的 CCR6 T 淋巴细胞。鉴于人类树突状细胞在婴儿期缺乏 IL-12（IL-17A 的有效抑制剂），我们进一步假设哮喘表型的发展最初不是由 Th2/Th1 细胞因子失衡介导的，而是由 IL-17A/IL-12 失衡介导的。为了检验这些假设，我们将 1) 研究婴儿气道上皮中 CCL20 表达的发育调节，2) 表征接触过敏原后婴儿猴肺中趋化因子受体 CCR6 淋巴细胞群的特征，以及 3) 确定 IL-17/IL-12 失衡对接触过敏原的婴儿猴的影响。本申请中提出的实验将有助于我们全面了解成熟的产后肺部上皮如何指导对吸入过敏原的病理性免疫反应的发展。我们关于 IL-17A 在非人类灵长类动物哮喘发展中的作用的研究结果可以直接推断用于预防儿童哮喘的候选药物的鉴定。本申请中提出的实验将有助于我们全面了解成熟的产后肺部上皮如何指导对吸入过敏原的病理性免疫反应的发展。我们关于 IL-17A 在非人类灵长类动物哮喘表型发展中的贡献的研究结果可以直接推断用于预防儿童哮喘的候选药物的鉴定。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Little is known about the antecedent events within the human infant lung that predispose the development of pathologic immune responses to inhaled allergens later in life. We do not know if the structural cells of the infant lung can significantly influence the phenotype of an immune response to an inhaled environmental challenge. Of particular significance is the epithelial cell of the conducting airways, which is architecturally and functionally poised to serve as a liaison to the adaptive immune system. The primary objective of this proposal is to determine how the conducting airway epithelium of the infant lung can influence the adaptive immune response to inhaled allergens. Our overall hypothesis is that epithelial cells of the infant lung play a central role in the initiation of the asthma phenotype, via constitutive CCL20 chemokine expression to promote airways recruitment of chemokine receptor CCR6+ T lymphocytes. This hypothesis is based on preliminary data obtained from airway epithelial cell cultures, demonstrating age-dependent expression and inhibitory microRNA regulation of CCL20 via IL-17A. We have also identified a population of IL-17A-producing CCR6+ T lymphocytes in airways of allergen-exposed infant monkeys. Given that human dendritic cells are deficient in IL-12 (a potent inhibitor of IL-17A) during infancy, we further hypothesize that development of the asthma phenotype is initially mediated not by an imbalance of Th2/Th1 cytokines, but rather an imbalance of IL-17A/IL-12. To test these hypotheses, we will 1) investigate the developmental regulation of CCL20 expression in infant airway epithelium, 2) characterize chemokine receptor CCR6+ lymphocyte populations in the infant monkey lung following allergen exposure, and 3) determine the impact of IL-17/IL-12 imbalance on allergen exposed infant monkeys. The experiments proposed within this application will contribute to our overall understanding of how the epithelium of the maturing postnatal lung can direct the development of a pathologic immune response to inhaled allergens. Our findings regarding the contribution of IL-17A in development of asthma in the non-human primate can be directly extrapolated towards identification of candidate drugs for the prevention of childhood asthma. The experiments proposed within this application will contribute to our overall understanding of how the epithelium of the maturing postnatal lung can direct the development of a pathologic immune response to inhaled allergens. Our findings regarding the contribution of IL-17A in the development of the asthma phenotype in non-human primates can be directly extrapolated towards identification of candidate drugs for the prevention of childhood asthma.