Basophil Histamine Releasability in Asthmatic Children

ABSTRACT

PURPOSE: The release of histamine from human basophils is controlled by an intrinsic, as yet unidentified, cellular property termed "releasability." We carried out this study to ascertain whether there was any difference in the releasability of basophils from asthmatic children compared to those from normal children. We intended also to clarify the correlation between the releasability and the atopic status of asthma. METHODS: We selected nineteen atopic asthmatic, eighteen nonatopic asthmatic and fourteen normal children for this study. Suspensions of leukocytes were isolated and stimulated with calcium ionophore A23187, anti-IgE and D. pteronyssinus antigen. After incubation, the supernatant was assayed for histamine with an automated fluorometric technique. RESULTS: Basophil histamine release with anti-IgE was different in three groups. Anti-IgE caused significantly more basophil histamine release in asthmatic children than in nomal children. Atopic asthmatic group showed greater basophil histamine release with anti-IgE than nonatopic asthmatic group. D. pteronyssinus antigen caused the significant amount of histamine release only in atopic asthmatic group. CONCLUSIONS: Our data suggests that basophils from asthmatic children are characterized by a specific increase in IgE mediated histamine releasability. The difference of histamine releasability with anti-IgE between atopic and nonatopic asthmatic children may be due to the heterogeneity of IgE bound to cell surface, or may be due to the degree of the basophil activation by cytokines such as IL3. The specific release of histamine with D. pteronyssinus antigen in atopic asthmatic group suggests that the basophil histamine release test can be used to diagnose the causing antigen.