Diesel-enriched particulate matter functionally activates human dendritic cells

Abstract Epidemiologic studies have associated exposure to airborne particulate matter (PM) with exacerbations of asthma. It is unknown how different sources of PM affect innate immunity. We sought to determine how car-and diesel exhaust–derived PM affects dendritic cell (DC) activation. DC development was modeled using CD34+ hematopoietic progenitors. Airborne PM was collected from exhaust plenums of Fort McHenry Tunnel providing car-enriched particles (CEP) and diesel-enriched particles (DEP).