Defining Molecular Phenotypes of Exacerbation Prone Asthmatics

病毒性哮喘急性发作导致180万急诊室就诊和40万 美国每年的住院人数都在增加，构成了重大的公共卫生问题和经济负担。人类 鼻病毒（HRV）是儿童和成人哮喘急性发作的主要诱因， 对这些病毒引起病情加重的机制知之甚少。本申请旨在 使用新的方法来识别可能进展为HRV感染加重的儿科患者， 并开发新的药物来防止病情恶化。在这些研究中，我们将比较100名有加重倾向的 哮喘儿童与几个对照队列，并纵向跟踪他们。对于每一个主题，我们将采样 他们的“环境暴露云”使用个人暴露监测器（项目1）。我们将决定如何 暴露云影响病情恶化，并确定产生病情恶化的成分， 最高频率将对受试者的鼻上皮进行采样，以确定其转录组学。 （项目2）。鼻上皮细胞也将在空气-液体界面培养物中生长，并且转录组 将在IL-13、烟草烟雾和HRV激发后进行分析。与此同时，我们将研究表观遗传 每个受试者的CD 4 + T细胞的景观，并确定分子编程如何调节 免疫活性导致哮喘加重（项目3）。我们还将探测串扰 上皮细胞和CD 4 + T细胞之间的关系，通过测试上皮细胞是否产生改变 淋巴细胞的表观遗传学上皮细胞和CD 4 +T细胞的分析将在 环境暴露和临床结果的背景。在项目4中，我们将研究 肺表面活性蛋白A（SP-A）和表面活性脂质，棕榈酰-油酰-磷脂酰甘油（POPG） 和磷脂酰肌醇（PI）作为HRV感染的抑制剂。的 将研究表面活性剂组分和HRV对上皮转录组的影响， 抑制剂影响宿主细胞转录模式的机制。我们还将确定抑制剂 调节调节CD 4 + T细胞促哮喘活性的上皮因子的产生。实验 与PI及其结构类似物和HRV的结合，以测试它们的体内抗病毒活性。 其他小鼠研究将使用屋尘螨免疫原和HRV 1B感染作为哮喘模型 加重磷脂作为哮喘急性发作抑制剂的有效性将被严格检验 使用老鼠模型。从这些研究中，我们希望确定重要的环境促进因素， 哮喘急性发作与心率变异性联合作用。我们还希望能够识别上皮转录组， 标签和CD 4 + T细胞转录组标签和表观遗传标志，将高度预测 哮喘恶化。我们对表面活性剂成分的研究将为我们提供有关 这些分子作为HRV诱导的哮喘恶化的预防剂和治疗剂的用途。

Viral exacerbations of asthma are responsible for 1.8 million emergency room visits and 0.4 million hospitalizations in the US each year, constituting a major public health problem and economic burden. Human rhinoviruses (HRVs) are the dominant instigators of asthma exacerbations in children and adults, but the mechanisms by which these viruses cause exacerbations are poorly understood. This application seeks to use new approaches to identify pediatric patients who are likely to progress to exacerbation with HRV infection, and develop new agents to prevent exacerbations. In these studies we will compare 100 exacerbation-prone asthmatic children with several control cohorts and follow them longitudinally. For each subject we will sample their “environmental exposure cloud” using personal exposure monitors (Project 1). We will determine how the exposure cloud influences exacerbations and identify the constituents that produce exacerbations with the highest frequency. Subjects will have their nasal epithelium sampled for determining their transcriptomic profiles (Project 2). Nasal epithelial cells will also be grown in air-liquid interface cultures and the transcriptome will be analyzed after IL-13, tobacco smoke and HRV challenge. In parallel, we will examine the epigenetic landscape of the CD4+ T cells from each subject and determine how molecular programming regulates the immune activity contributing to exacerbation-prone asthma (Project 3). We will also probe for crosstalk between epithelial cells and CD4+ T cells by testing if the epithelial cells produce factors that alter the epigenetics of the lymphocytes. The analyses of epithelial cells and CD4+T cells will be examined in the context of environmental exposures and clinical outcomes. In project 4 we will examine the activity of pulmonary surfactant protein A (SP-A) and the surfactant lipids, palmitoyl-oleoyl-phosphatidylglycerol (POPG) and phosphatidylinositol (PI) as inhibitors of HRV infections using patient epithelial cells in culture. The effects of surfactant components and HRV upon the epithelial transcriptome will be investigated to identify mechanisms by which inhibitors affect host cell transcription patterns. We will also determine if the inhibitors regulate the production of epithelial factors that modulate CD4+ T cell pro-asthmatic activity. Experiments with PI and its structural analogs, and HRV, will be conducted in mice to test their in vivo anti-viral activity. Additional mouse studies will use a house dust mite immunogen and HRV1B infection as a model for asthma exacerbations. The efficacy of phospholipids as suppressors of asthma exacerbations will be critically tested using the mouse model. From these studies we expect to identify important environmental promoters of asthma exacerbation that work in combination with HRV. We also expect to identify epithelial transcriptomic signatures and CD4+ T cell transcriptomic signatures and epigenetic landmarks that will be highly predictive of asthma exacerbations. Our studies with surfactant constituents will provide us with information about the utility of these molecules as preventives and therapeutics for HRV induced asthma exacerbations.