Mechanisms of Response to Diesel Exhaust in Subjects With Asthma

The investigators will also characterize selected polymorphisms in glutathione-S-transferase (GST) genes that have been implicated in susceptibility to air pollutants. Outcome measures will include lung function, bronchial responsiveness to bronchodilator, exhaled nitric oxide, induced sputum for inflammatory markers (IL6 and IL8), and exhaled breath condensate for nitrite, 8-isoprostane, 20-HETE (20-hydroxyeicosatetraenoic acid), nitrotyrosine and pH. In this pilot project, parallel studies are being carried out in the human exposure chambers at two NIEHS centers, the EOHSI-CEED (Environmental and Occupational Health Sciences Institute- Center for Environmental Exposure and Disease) and the Penn-CEET (University of Pennsylvania-Center of Excellence in Environmental Toxicology). The joint project will enable each center to validate research results in a second population and include new biomarkers of pulmonary inflammation. Each center will recruit, consent, and collect data on its own subjects. Only de-identified data will be shared between the centers.