Title: Inhalation of concentrated ambient particulate matter near a heavily trafficked road stimulates antigen-induced airway responses in mice.
Authors: Kleinman, Michael T; Hamade, Ali; Meacher, Dianne; Oldham, Michael; Sioutas, Constantinos; Chakrabarti, Bhabesh; Stram, Dan; Froines, John R; Cho, Arthur K
Published In J Air Waste Manag Assoc, (2005 Sep)
Abstract: The goal of this study was to test the following hypotheses: (1) exposure to mobile emissions from mobile sources close to a heavily trafficked roadway will exacerbate airway inflammation and allergic airway responses in a sensitized mouse model, and (2) the magnitude of allergic airway disease responses will decrease with increasing distance from the roadway. A particle concentrator and a mobile exposure facility were used to expose ovalbumin (OVA)-sensitized BALB/c mice to purified air and concentrated fine and concentrated ultrafine ambient particles at 50 m and 150 m downwind from a roadway that was heavily impacted by emissions from heavy duty diesel-powered vehicles. After exposure, we assessed interleukin (IL)-5, IL-13, OVA-specific immunoglobulin E, OVA-specific immunoglobulin G1, and eosinophil influx as biomarkers of allergic responses and numbers of polymorphonuclear leukocytes as a marker of inflammation. The study was performed over a two-year period, and there were differences in the concentrations and compositions of ambient particulate matter across those years that could have influenced our results. However, averaged over the two-year period, exposure to concentrated ambient particles (CAPs) increased the biomarkers associated with airway allergies (IL-5, immunoglobulin E, immunoglobulin G1 and eosinophils). In addition, mice exposed to CAPs 50 m downwind of the roadway had, on the average, greater allergic responses and showed greater indications of inflammation than did mice exposed to CAPs 150 m downwind. This study is consistent with the hypothesis that exposure to CAPs close to a heavily trafficked roadway influenced allergic airway responses.
PubMed ID: 16259423
MeSH Terms: Air Pollutants/toxicity*; Animals; Bronchoalveolar Lavage Fluid/chemistry; Bronchoalveolar Lavage Fluid/cytology; California; Eosinophils/cytology; Immunoglobulin E/blood; Immunoglobulin G/blood; Inhalation Exposure; Interleukin-13/biosynthesis; Interleukin-5/biosynthesis; Los Angeles; Lung/drug effects*; Lung/immunology; Male; Mice; Mice, Inbred BALB C; Neutrophils/cytology; Ovalbumin/immunology; Respiratory Hypersensitivity/chemically induced*; Respiratory Hypersensitivity/immunology; Vehicle Emissions/toxicity*