PAF-INDUCED EOSINOPHIL CHEMOTAXIS INCREASES DURING AN ASTHMATIC ATTACK AND IS INHIBITED BY PREDNISOLONE IN-VIVO AND IN-VITRO

We investigated platelet-activating factor (PAF)-induced migration in eosinophils obtained from asthmatic patients who were treated with dir without intravenous prednisolone. The migration of asthmatic eosinoph ils in remission and during an attack was significantly greater than t hat in healthy volunteers. The migration of asthmatic eosinophils expo sed to prednisolone in vivo and in vitro was significantly inhibited, compared to asthmatic eosinophils not exposed to prednisolone. These f indings suggest that an intracellular factor causes asthmatic eosinoph ils to migrate, and that prednisolone inhibits PAF-induced eosinophil migration. (C) 1997 Academic Press.