[Inhibitory effect of AS-35. a novel antiallergic drug, on chemical mediator release from human eosinophils].

To determine whether AS-35, a new antiallergic drug, inhibits the activation of eosinophils, we examined the effect of AS-35 on the release of leukotriene C4 (LTC4) and eosinophil peroxidase (EPO) from human eosinophils. Calcium ionophore A23187 caused both LTC4 and EPO release from human eosinophils. AS-35 (1 x 10(-5) M) inhibited A23187-induced LTC4 release from the eosinophils with 56% inhibition. AS-35 (1 x 10(-6) to 1 x 10(-5) M) also inhibited A23187-induced EPO release from the eosinophils in a dose-dependent fashion with 79% inhibition at 1 x 10(-5) M. We concluded that AS-35 prevents the activation of human eosinophils to inhibit LTC4 and EPO release. These results suggest that AS-35 might be useful in controlling allergic diseases by inhibiting eosinophil activation.