Defining Molecular Phenotypes of Exacerbation Prone Asthmatics

病毒性哮喘加重导致180万急诊室就诊和40万人次 美国每年的住院人数，构成了一个重大的公共卫生问题和经济负担。人类 鼻病毒(HRV)是儿童和成人哮喘恶化的主要煽动者，但 人们对这些病毒导致病情恶化的机制知之甚少。此应用程序旨在 使用新的方法来识别可能进展为HRV感染恶化的儿科患者， 并开发新的药物以防止病情恶化。在这些研究中，我们将比较100个易加重的 哮喘儿童与几个对照队列，并纵向跟踪他们。对于每个主题，我们都会进行抽样 他们使用个人暴露监测器的“环境暴露云”(项目1)。我们将决定如何 暴露云会影响病情恶化，并通过 最高频率。受试者将对他们的鼻黏膜上皮进行采样，以确定他们的转录水平 配置文件(项目2)。鼻腔上皮细胞也将在气液界面培养和转录组中生长。 将在IL-13、烟草烟雾和HRV激发后进行分析。同时，我们将研究表观遗传学 每个受试者的CD4+T细胞的情况，并确定分子编程如何调节 免疫活动导致易加重的哮喘(项目3)。我们还将探索串扰 通过测试上皮细胞是否产生改变T细胞的因子 淋巴细胞的表观遗传学。对上皮细胞和CD4+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，我们将检查以下活动 肺表面活性物质蛋白A(SP-A)和表面活性物质脂-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，使用患者上皮细胞进行培养。这个 表面活性成分和HRV对上皮转录组的影响将被研究以确定 抑制物影响宿主细胞转录模式的机制。我们还将确定这些抑制剂是否 调节调节CD4+T细胞哮喘前活性的上皮因子的产生。实验 与PI及其结构类似物，以及心率变异性，将在小鼠身上进行测试，以测试其体内的抗病毒活性。 更多的小鼠研究将使用屋尘螨免疫原和HRV1B感染作为哮喘的模型 病情加重。磷脂抑制哮喘恶化的有效性将受到严格的检验。 使用鼠标模型。从这些研究中，我们希望确定重要的环境促进者 哮喘加重与心率变异性的共同作用。我们还希望确定上皮转录 签名和CD4+T细胞转录签名和表观遗传标志将高度预测 哮喘加重。我们对表面活性剂成分的研究将为我们提供关于 这些分子在HRV诱导的哮喘加重中的预防和治疗作用。

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.