In vitro influence of theophylline on anti-IgE-induced release from leucocytes and whole blood in asthmatic children.

Two groups of asthmatic children were found with regard to the influence of theophylline on the anti-IgE-induced histamine release from whole blood. In th first group (21 children), histamine release was obtained both from whole blood and washed leucocytes and was inhibited by 10(-4) M theophylline. In the second group (5 children), histamine release required the presence of plasma and was not inhibited by 10(-4) M theophylline. Theophylline treatment was efficacious only in children of the first group.