Inhibition of human cutaneous anaphylaxis by cytochalasin B.

The effect of cytochalasin B (which selectively inhibits the function of cytoplasmic contractile microfilaments) on IgE-mediated hypersensitivity in human skin was studied. Cytochalasin B inhibited the antigen-induced histamine release from human skin slices sensitized passively in vitro with human reaginic serum. The magnitude of inhibition of histamine release was related to the duration of preincubation of sensitized skin slices with cytochalasin B. The effect of cytochalasin B on antigen-induced histamine release from sensitized skin was reversible, indicating that the inhibition of histamine release may be due to the inhibition of contraction of cytoplasmic microfilaments in sensitized target cells by cytochalasin B.