Viral exacerbation of chronic airway inflammation in BALB/c mice sensitized with house dust mite (HDM): a role for corticosteroids?

Materials and methods Male BALB/c mice were sensitized to purified house dust mite extract (HDM; 25 μg) without exogenous adjuvant 5 days/week for 5 weeks (day 0-32). On day 21 designated groups were treated with fluticasone propionate (F; 10ug/animal, BID) until the end of the study. On day 35, designated groups were instilled with influenza (IFZ; A/HKx31[H3N2]; 10 PFU). On day 39 (4 days pi) and 49 (14 days pi), groups were evaluated for airway hyperreactivity (AHR), lung inflammation (BAL), viral titer, and histopathology.