Cytokine Profiles In Bronchoalveolar Lavage In a Mouse Model Of Bronchial Asthma During A(H1N1)pdm09 and Seasonal H1N1 Infection

Many reports have shown that A(H1N1)pdm09 infection induced severe pulmonary complications. Bronchial asthma is thought to be one of the risk factors that exacerbate respiratory symptoms of A(H1N1)pdm09-infected patients. However the pathogenesis remains unclear. We induced mouse models of bronchial asthma using ovalbumin and infected with A(H1N1)pdm09 or seasonal H1N1 (1x105 pfu/mouse) intranasally. We analyzed cytokine profiles in bronchoalveolar lavage (BAL) in the mouse models, and compared them between asthma mice and non-asthma mice on the day 7 after infection. We also determined their virus titers on day 7 after infection. The levels of interleukin (IL)-6, IL-10 and tumor necrosis factor (TNF)-α in asthma mice infected with A(H1N1)pdm09 were significantly higher than those in non-asthma mice on day 7 postinfection. On the other hand, those levels of in asthma mice infected with seasonal H1N1 were significantly lower than those in non-asthma mice after the viral infection. In addition, virus titers in BAL in asthma mice infected with A(H1N1)pdm09 were also significantly higher than those in the non-asthma mice, but not seasonal H1N1 infection. Our results suggest that A(H1N1)pdm09 infection may induce more severe pulmonary inflammations and increase replications of virus in patients with bronchial asthma, compared with healthy individuals, unlikely seasonal H1N1 infection.