Effects of ambient air particulate matter on the airway inflammation in murine model of asthma

Abstract

Background Although epidemiologic studies have shown that high ambient air particulate matter (PM) concentration is associated with increased risk of asthma exacerbation, the role of PM on airway inflammation in asthma is poorly understood. Method PM was collected using high-volume air sampler in Incheon, Korea and was suspended in PBS. To induce the phenotype of asthma, BALB/c mice were sensitized with intraperitoneal administration of ovalubmin (OVA) and alum, and challenged with OVA with or without PM. Effect of PM administration during OVA challenge in OVA sensitized mice and na?ve mice were evaluated by measurement of airway hyperresponsiveness (AHR), inflammatory cell count in bronchoalveolar lavage (BAL) fluid, and lung histology. Results Treatment of PM with OVA in OVA sensitized mice showed significant increase in AHR without change in inflammatory cell count in BAL fluid or histology, compared to PM-nontreated mice with asthma. Exposure to same dose of PM in na?ve mice did not induce significant change in AHR and airway inflammation. Conclusion These findings suggest PM plays an important role in aggravation of asthma in sensitized subject at the concentration of minimal effect in healthy subject.