Effect of influenza virus infection in a murine model of asthma

Respiratory virus infection is a major cause of asthma exacerbation. however,the underlying mechanisms of this exacerbation are unknown. therefore,to determine the mechanisms,we examined the effect of influenza infection in a murine model of asthma. mice were divided into four groups: the phosphate-buffered saline (pbs),house dust mite (hdm),influenza,and hdm/influenza groups. the influenza group and the hdm/influenza group were infected with influenza a virus. we measured airway resistance (penh value),examined the lung tissue for pathology,and analyzed the cells and cytokines in bronchoalveolar lavage fluid (balf) by elisa. at 50 mg/ml methacholine,the hdm/influenza group showed a significantly higher penh value than the pbs,hdm,and influenza groups. the number of neutrophils in balf was higher in the hdm/influenza group than in the hdm group. a significantly greater number of lymphocytes and macrophages were detected in the hdm/influenza group than in the hdm group. ifn-γ and il-1β levels were higher in the hdm/influenza group than in the hdm group. il-5 levels did not vary between the hdm and hdm/influenza groups,il-10 was significantly lower in the hdm/influenza than in the hdm group. chemokine (c-x-c motif) ligand 1 (cxcl1) and regulated upon activation,normal t cell expressed and secreted (rantes) were higher in the hdm/influenza group than in the hdm group. in a murine model of asthma,influenza-induced airway inflammation appeared to be caused by simultaneous activation of neutrophilic and eosinophilic inflammation. copyright© summer 2015,iran j allergy asthma immunol. all rights reserved.