Selective inhibition of IgE-dependent histamine release in basophils by dasatinib. Dextran-enriched basophils from a healthy donor were preincubated with dasatinib (1 μM; ▲) or control medium (■) for 30 minutes. Then, cells were exposed to control buffer (co) or to various concentrations of anti-IgE (0.001-1 μg/mL, A), recombinant (r) C5a (0.1-100 nM) (B), or Ca-ionophore A23187 (0.01-10 μg/mL, C) for 30 minutes. After centrifugation, histamine was measured in supernatants and cell lysates by RIA. Results show the percentages of released histamine (relative to total histamine content) and represent the means (± SD) from triplicates in one donor. Identical results were obtained in a second donor.