A NOVEL ANTIALLERGIC DRUG, BETOTASTINE BESILATE, SUPPRESSES INTERLEUKIN-5 PRODUCTION BY HUMAN PERIPHERAL-BLOOD MONONUCLEAR-CELLS

The effect of a novel anti-allergic drug, betotastine besilate (betota stine) on interleukin (IL)-5 production by human peripheral blood mono nuclear cells (PBMC) was investigated. PBMC of Dermatophagoides farina e extract (Df)-sensitive donors produced IL-5 and showed a proliferati ve response upon stimulation with relevant antigen (10 mu g/ml). Df-in duced IL-5 production by PBMC was significantly inhibited by betotasti ne at 10 and 100 mu M. Betotastine also suppressed proliferation of PB MC with less potency. The effect of betotastine on IL-5 production was enhanced and significant even at 0.1 mu M when the drug was added 120 min before antigen stimulation. Ketotifen and cetirizine also inhibit ed IL-5 production, but the effects of these drugs were significant on ly at 100 mu M. These findings indicate that the suppression of IL-5 p roduction may be involved in the anti-allergic effect of betotastine.