Increased sensitivity to the consequences of rhinoviral infection in atopic subjects.

cultured with cytomix (p<0.05, all comparisons) and each was decreased by dexamethasone 10-6 M (p<0.05, all comparisons). To determine if these in vitro observations are reflected in vivo, exhaled NO was measured in 64 normal subjects, 22 asthmatics not taking corticosteroids, and 36 asthmatics taking inhaled corticosteroids. Peak exhaled NO levels were increased in asthmatics not taking corticosteroids compared to normal control subjects (p<0.01) butnot in asthmatics taking corticosteroids (p>0.05). These data demonstrate that cytokines increase iNOS expression by lung epithelial cells which is decreased by corticosteroids and that these in vitro observations are mirrored by exhaled NO levels in asthmatics.