Further Studies on the Thermostable Leukocytosis Factor of Exudates

Abstract

The thermostable leukocytosis factor, recovered especially from acid exudates, and found in association with the pyrogenic factor, pyrexin, was crystallized,and the crystals as such have essentially neither pyrogenic nor leukopenic properties. The crystals of the thermostable leukocytosis factor induce a leukocytosis characterized by a discharge into the circulation of immature l-lobe form of granulocytes.