EFFECTS OF INHALED BUDESONIDE ON ALLERGEN-INDUCED AIRWAY RESPONSES AND AIRWAY INFLAMMATION

Allergen inhalation by sensitized subjects results in acute bronchocon striction, which can be followed by a later bronchoconstrictor respons e, allergen-induced airway hyperresponsiveness, and increases in airwa y inflammatory cells. Treatment with inhaled glucocorticosteroids atte nuates allergen-induced asthmatic airway responses. The purpose of thi s study was to determine whether a 1-wk pretreatment with inhaled bude sonide influences allergen-induced changes in inflammatory cells in bl ood and induced sputum. Seven subjects with mild atopic asthma were tr eated in a double-blind, placebo-controlled, randomized, crossover fas hion with either inhaled budesonide 400 mu g/d, or placebo for 7 d. Al lergen challenges were carried out the morning after treatment was dis continued and sputum samples were obtained 7 h after allergen inhalati on. Methacholine airway responsiveness was measured, and blood and spu tum samples were obtained 24 h post-allergen. Budesonide treatment att enuated the magnitude of both the early and the late asthmatic respons e, reduced allergen-induced methacholine airway hyperresponsiveness, a nd attenuated allergen-induced increases in total eosinophils and acti vated eosinophils. These results suggest that the effects of inhaled g lucocorticosteroids on allergen-induced airway responses may be mediat ed through their inhibition of allergen-induced eosinophil migration a nd activation.