Project 2

项目2 项目2是一个新的生物医学研究项目，旨在开发新的工具，以快速表征儿科 暴露于有害挥发性有机化合物（VOC）的呼吸系统健康风险。这项工作将是 德克萨斯A&M大学超级基金研究中心整体战略的关键要素， 管理与接触环境紧急情况相关的人类健康风险 物质.目前的毒性测试策略没有考虑发育阶段，这是代表 小儿肺或包括人类群体变异性，即使这些因素（即，年龄性别种族 和遗传学）在哮喘风险中至关重要。此外，单个/组合VOC的作用机制 对哮喘的发病机制了解甚少。支持有害VOC的评估，包括真实的 城市混合物，并阐明机械联系，项目2将测试假设，即小儿气道是 明显易受有害VOC的肺损伤，气道反应受 细胞外囊泡（EV）介导的信号传导。研究小组召集了一位毒理学家，一位医生- 科学家和大气化学家，以解决以下具体目标。目标1优先评价 20个超级基金优先的VOC体外测试哮喘相关表型，首先使用呼吸道 上皮细胞系（16 HBE）在气液界面培养，然后在基于群体的、年龄合适的模型中 由来自发育中肺分子图谱计划的小儿支气管上皮细胞组成。接下来， 与环境空气中化学品的环境相关比例相匹配的代表性设计混合物将 在标准和基于人群的儿科细胞系中进行评估。这些答复将为目标2提供信息 机制研究，将测试VOC暴露改变EV蛋白表达的假设， 呼吸功能障碍已知炎症和上皮屏障功能由外来体介导， 一类分泌型EV，范围为30至150 nm。在目的2中，将源自暴露于选择性细胞的16 HBE细胞的EV VOC/混合物将使用高通量蛋白质组学方法进行纯化和测序。蛋白质特征 然后将在不同的儿科供体细胞系中验证该模型中揭示的结果。最后，职能作用 将使用过继转移实验评价VOC暴露的细胞衍生EV。与目标1和 2、目标3的目标将通过对不同地点的移动的空气监测来表征挥发性有机化合物混合物， 在基线期间和应对环境灾害期间，大休斯顿地区。此外，为了填补 与灾难相关的毒性测试，16 HBE电池将直接暴露于移动的平台上的环境空气中 在现场，使用时间分辨测量来驱动不同气团的条件采样。成果 项目2中提出的研究与超级基金计划高度相关。总的来说，新的工具和 研究结果将提高对VOC引起的儿童肺损伤机制的基本理解 并能够改进风险评估，以快速确定威胁儿童健康的呼吸道危害。

Project 2 ABSTRACT Project 2 is a new Biomedical Research Project aimed at developing novel tools to rapidly characterize pediatric respiratory health risks from exposure to hazardous volatile organic compounds (VOCs). This work will be a critical element in the overall strategy of the Texas A&M University Superfund Research Center to characterize and manage the human health risks associated with exposure to environmental emergency-mobilized hazardous substances. Current toxicity testing strategies do not account for developmental stage that is representative of the pediatric lung or encompass human population variability, even though these factors (i.e., age, sex, race, and genetics) are critical in asthma risk. Moreover, mechanisms of action underlying individual/combined VOCs on asthma pathogenesis is poorly understood. To support the evaluation of hazardous VOCs, including real urban mixtures, and elucidate mechanistic linkages, Project 2 will test the hypothesis that the pediatric airway is distinctly susceptible to pulmonary injury from hazardous VOCs, and that airway responses are modulated by extracellular vesicle (EV)-mediated signaling. The research team brings together a toxicologist, a physician- scientist and an atmospheric chemist to address the following specific aims. Aim 1 prioritizes the evaluation of 20 individual Superfund-priority VOCs to test for asthma-related phenotypes in vitro, first using a respiratory epithelial cell line (16HBE) cultured at air-liquid interface, and then in a population-based, age-appropriate model comprised of pediatric bronchial epithelial cells from the Developing Lung Molecular Atlas Program. Next, representative designed mixtures matching environmentally-relevant proportions of chemicals in ambient air will be evaluated in the standard and population-based pediatric cell lines. These responses will inform aim 2 mechanistic studies, which will test the hypothesis that VOC exposures alter EV protein expression, underlying respiratory dysfunction. It is known that inflammation and epithelial barrier function are mediated by exosomes, a class of secreted EVs ranging from 30 to 150 nm. In aim 2, EVs derived from 16HBE cells exposed to select VOCs/mixtures will be purified and sequenced using a high-throughput proteomics approach. Protein signatures revealed in this model will then be validated across diverse pediatric donor cell lines. Last, the functional role of VOC-exposed, cell-derived EVs will be evaluated using adoptive transfer experiments. In parallel to aims 1 and 2, aim 3 objectives will characterize VOC mixtures through mobile air monitoring across different locations in the greater Houston Area during baseline and in response to environmental disasters. Additionally, to fill in gaps in disaster-related toxicity testing, 16HBE cells will be directly exposed to ambient air onboard the mobile platform in the field, using time-resolved measurements to drive conditional sampling of different air masses. Outcomes from the studies proposed in Project 2 are highly relevant to the Superfund Program. Overall, the novel tools and findings will improve basic understanding of mechanisms underlying VOC-induced pediatric pulmonary injury and enable improved risk assessment to rapidly characterize respiratory hazards that threaten children’s health.