Transcriptional Programming of Asthma Related Pathology in Respiratory Epithelia

描述(申请人提供)：这项新的申请寻求资金，以确定和定义一个转录网络，该网络确定与哮喘和其他慢性肺部疾病的发病机制有关的呼吸上皮细胞(REC)分化、杯状细胞增生和TH2样肺表型。这一应用是基于新的数据，该数据证明了由ETS家族成员、SPDEF(SAM指向结构域ETS样因子)和FOXA2组成的转录网络在调节杯状细胞分化和肺中TH2样过程中的关键作用。我们的初步数据表明，呼吸道上皮细胞的分化是由FOXA2和SPDEF调节的内在转录程序介导的，反过来，FOXA2和SPDEF又驱动杯状细胞增殖、嗜酸性趋化因子和TH2细胞因子从呼吸道上皮细胞表达。这项应用将利用转基因小鼠模型、生物信息学、呼吸道上皮细胞体外培养和生物化学来确定控制肺内固有杯状细胞程序的机制，以及呼吸道上皮决定小鼠肺中哮喘相关表型的机制。目的1验证转录因子FOXA2在呼吸道上皮细胞分化、调控杯状细胞增殖和TH2样炎症相关基因表达中的重要作用。FOXA2和FOXA3差异调节呼吸道基因表达的机制将被确定。目的2将验证这样的假设，即SPDEF是一种ETS样因子，在传导气道中表达，部分通过FOXA2调节杯状细胞的分化。目的研究SPDEF基因缺失在呼吸道上皮细胞分化、基因表达及对肺变应原和IL-13刺激反应中的作用，验证SPDEF在IL-13/变应原诱导的杯状细胞分化中所必需的假说。申请人长期以来一直对发育中的肺泡上皮的细胞和分子生物学研究感兴趣，最近正在将这些方法应用于传导呼吸道上皮细胞生物学的研究。这一应用是基于鉴定了一种新的转录网络，该网络驱动呼吸道上皮中的杯状细胞增殖和TH2样炎症。这些研究将对杯状细胞增生和哮喘的发病机制提供深入的认识，并将为开发诊断和治疗慢性呼吸系统疾病的新策略提供基础，包括哮喘、囊性纤维化和慢性阻塞性肺疾病。公共卫生相关性：杯状细胞增生、炎症和组织重塑伴随常见的慢性呼吸系统疾病，包括哮喘、慢性阻塞性肺疾病和慢性阻塞性肺疾病。该应用旨在确定由FOXA2和SPDEF介导的新的转录网络的作用，该网络调节呼吸道上皮细胞的分化，进而影响炎症和与这些慢性肺疾病相关的固有宿主防御。这项工作将确定调节呼吸道上皮稳态的机制，将为诊断和影响影响呼吸道的慢性肺部疾病的发病机制提供新的靶点。

DESCRIPTION (provided by applicant): This new application seeks funding to identify and define a transcriptional network that determines Respiratory Epithelial Cell (REC) differentiation, goblet cell hyperplasia, and TH2-like pulmonary phenotypes related to the pathogenesis of asthma and other chronic pulmonary disorders. The application is based on novel data demonstrating the critical roles of a transcriptional network consisting of an Ets family member, SPDEF (SAM pointed domain ets-like factor) and FOXA2 in the regulation of goblet cell differentiation and TH2- like processes in the lung. Our preliminary data demonstrate that differentiation of epithelial cells in conducting airways, is mediated by an intrinsic transcriptional program regulated by FOXA2 and SPDEF that, in turn, drives goblet cell hyperplasia, eosinophilic chemokine, and TH2 cytokine expression from the respiratory epithelium. The application will utilize transgenic mouse models, bioinformatics, in vitro cultures of airway epithelial cells, and biochemistry to determine mechanisms controlling the intrinsic goblet cell program in the lung, and mechanisms by which the respiratory epithelium determines asthma related phenotypes in the mouse lung. Aim 1 will test the hypothesis that the transcription factor FOXA2 plays a critical role in conducting airway epithelial cell differentiation, regulating goblet cell hyperplasia and the expression of genes mediating TH2-like inflammation. Mechanisms by which FOXA2 and FOXA3 differentially regulate gene expression in the respiratory tract will be identified. Aim 2 will test the hypothesis that SPDEF, an ets-like factor, expressed in conducting airways, regulates goblet cell differentiation, in part, via FOXA2. Aim 3 will determine the role of Spdef gene deletion on respiratory epithelial cell differentiation, gene expression, and response to pulmonary allergen and IL-13 challenge, testing the hypothesis that Spdef is required for IL-13/allergen induced goblet cell differentiation. The applicant has had a long-standing interest in study of the cellular and molecular biology of the developing alveolar epithelium, and is recently applying these approaches to the study of conducting airway epithelial cell biology. This application is based on the identification of a novel transcriptional network driving goblet cell hyperplasia and TH2-like inflammation from the respiratory epithelium. These studies will provide insights into the pathogenesis of goblet cell hyperplasia and asthma, and will provide basis for the development of new strategies to diagnose and treat chronic respiratory diseases, including asthma, cystic fibrosis, and chronic obstructive pulmonary disease. PUBLIC HEALTH RELEVANCE: Goblet cell hyperplasia, inflammation, and tissue remodeling accompany common chronic respiratory disorders, including asthma, CF, and COPD. This application seeks to determine the role of a novel transcriptional network, mediated by FOXA2 and SPDEF, that regulates epithelial cell differentiation in the airways that, in turn, influences inflammation and innate host defense associated with these chronic pulmonary disorders. The work will identify mechanisms regulating airway epithelial homeostasis that will provide novel targets to diagnose and influence the pathogenesis of chronic pulmonary diseases affecting the airways.