Figure 1.

Effect of FK506 and cyclosporine on histamine release from (a) mast cells and (b) basophils. Cells were incubated (5 min) with either inhibitor before activation with anti-IgE. Results are expressed as the % inhibition of the control histamine releases which were 27±3% (mast cells) and 28±3% (basophils). Statistically significant (P<0.01) levels of inhibition were obtained for FK506 (⩾0.01 nM) and cyclosporine (⩾0.1 μM). Values are means±s.e.m. for eight (mast cells) and 10 (basophils) experiments.