The Oxidative Burst and Related Phenomena in Mouse Macrophages Elicited by Different Sterile Inflammatory Stimuli

Abstract

Mouse peritoneal macrophages (MPM) elicited by paraffin oil (PO) or thioglycollate (TG) were compared in their capacity to generate oxidative burst (OB) products such as superoxide ion (O 2 −) and hydrogen peroxide (H 2O 2) and lyse target erythrocytes. Strong OB stimulants such as 12-O-tetradecanoyl-phorbol-13-acetate (TPA), opsonized zymosan, and wheat-germ agglutinin (WGA) were found to stimulate O 2 − and H 2O 2 production by both PO- and TG-elicited MPM. PO-elicited MPM exhibited a vigorous OB response compared to TG-elicited MPM and showed a higher degree of self iodination in the presence of 125I. Macrophage-mediated cytolysis of 51Cr-labeled red blood cells, following OB stimulation, was revealed by PO-elicited MPM triggered by TPA, opsonized zymosan, WGA, and Concanavalin A. TG-elicited MPM failed to respond to TPA and opsonized zymosan. In the presence of horseradish peroxidase, both PO- and TG-elicited MPM exhibited augmented cytocidal activities upon stimulation with TPA, whereas catalase abrogated the capacity of TPA-stimulated MPM to lyse red blood cells, which may suggest the involvement of H 2O 2 in the lytic process.