The Function of the Eosinophile Leukocyte

Abstract 1. Eosinophilia has been produced experimentally in guinea pigs by the injection of extracts of Ascaris suum and histamine, the accompanying histologic changes, particularly the distribution of eosinophils, being noted. 2. The tissues of guinea pigs suffering from a natural eosinophilia have been studied and compared with those of experimental eosinophilia. 3. From these findings a path has been traced which, it is suggested, the eosinophil follows in its course through the body. 4. The function of the eosinophil has been discussed and the hypothesis advanced that its function is the carriage of histamine or a histamine-like toxic material for inactivation. 5. This viewpoint has been considered in relation to the occurrence in man of eosinophilia including eosinophilic infiltration of the lungs.