Abstract
We investigated the effects of interleukin-3 (IL-3) on histamine release (direct releasing and indirect enhancing effects) from basophils in allergic asthmatic subjects. Interleukin-3 caused direct histamine release (HR) in selected donors (IL-3 responders) and enhanced anti-IgE-induced HR in other IL-3 nonresponders, although both direct releasing and indirect enhancing activities of IL-3 on HR did not coexist with each other. There was a significant correlation between IL-3-induced HR and spontaneous histamine release (r = .8532, P <.0001).