Cigarette smoke dissociates inflammation and lung remodeling in OVA-sensitized and challenged mice

We evaluated the effects of cigarette smoke (CS) on lung inflammation and remodeling in a model of ovalbumin (OVA)-sensitized and OVA-challenged mice. Male BALB/c mice were divided into 4 groups: non-sensitized and air-exposed (control); non-sensitized and exposed to cigarette smoke (CS), sensitized and air-exposed (OVA) (50 mu g + OVA 1% 3 times/week for 3 weeks) and sensitized and cigarette smoke exposed mice (OVA + CS). IgE levels were not affected by CS exposure. The increases in total bronchoalveolar fluid cells in the OVA group were attenuated by co-exposure to CS, as were the changes in IL-4, IL-5, and eotaxin levels as well as tissue elastance (p < 0.05). In contrast, only the OVA + CS group showed a significant increase in the protein expression of IFN-gamma, VEGF, GM-CSF and collagen fiber content (p < 0.05). In our study, exposure to cigarette smoke in OVA-challenged mice resulted in an attenuation of pulmonary inflammation but led to an increase in pulmonary remodeling and resulted in the dissociation of airway inflammation from lung remodeling. (C) 2012 Elsevier B.V. All rights reserved