Allergen- and anti-IgE-induced histamine release from whole blood.

The release of histamine by allergen and anti-IgE from whole blood was observed in 34 asthmatic subjects with a positive skin test to house dust. The time course of histamine release showed that the release by allergen and anti-IgE peaked after 15 min incubation. There was no significant difference in the time course of the release from whole blood between allergen and anti-IgE. Anti-IgE-induced histamine release correlated to a certain extent with the serum IgE level. Histamine release by house dust, on the other hand, correlated with the radioallergosorbent test score. A striking difference was present in the dose-response slope between allergen and anti-IgE. The maximum percent release correlated with the dose-response slope by allergen, but not by anti-IgE. The amount of histamine release induced by anti-IgE paralleled the amount of the release by house dust in the cases sensitive to the allergen; less sensitive basophils to anti-IgE were less sensitive to house dust.