RESUMEN
OBJECTIVE: To evaluate the basophil histamine releasability in response to IgE- and non- IgE-mediated stimuli in children with atopic asthma. Met: Basophil histamine releasability was measured in Dermatophagoides farinae (D. farinae)-sensitive atopic asthmatics, D.farinae-sensitive healthy atopics, non-atopic asthmatics, and healthy non-atopics. Basophils were stimulated with D.farinae, goat antihuman IgE antibody, formyl-Met-Leu-Phe(fMLP), and Calcium ionophore A23187. Histamine was measured by automated fluorometric technique. RESULTS: Sponianeous histamine release was higher in atopic asthmatics compared to healthy non-atopics. Histamine release by D.farinae and by anti-IgE antibody was higher in atopic asthmatics compared to the other groups. There was no difference in histamine release by fMLP among all groups. Histamine release by Calcium ionophore was higher in healthy atopics and non-atopic asthmatics compared to healthy non-atopics. The atopics showed correlation between histamine release by D.farinae, by anti-IgE antibody and total serum IgE levels. CONCLUSIONS: Spontaneous and IgE-mediated histamine release were related to the presence of both atopy and asthma, whereas non-IgE mediated histamine release was different depending on the stimuli.