PAF- and LTB4-induced migration of eosinophils and neutrophils isolated from horses with allergic skin disease

Abstract

Platelet activating factor (PAF) and leukotriene (LT)B4 cause thein vitro migration of equine granulocytes. In this study eosinophils and neutrophils have been prepared from horses showing clinical signs of the allergic skin disease sweet itch. Migratory responses have been compared to those of cells from normal animals. Cell migration was measured in a 48-well microchemotaxis chamber. PAF and LTB4 caused the migration of neutrophils and eosinophils from both allergic and normal horses. However, responses of eosinophils, but not neutrophils, from allergic horses were significantly reduced (p<0.05,n=5). No difference was observed between the random movement of neutrophils or eosinophils from normal and allergic horses. These results suggest that the migratory responses to PAF and LTB4 of eosinophils from allergic horses are down-regulated.