Oxidative metabolism of human peripheral blood eosinophils and neutrophils: H2O2 production after stimulation with phorbol myristate acetate and immune complexes.

Eosinophils like neutrophils possess an oxidative metabolism which is activated by phagocytosis and cell membrane activation. Since eosinophils may take part in inflammatory reactions by releasing oxygen species and have membrane receptors for immunoglobulins, immune complexes may activate their respiratory burst. We compared the ability of phorbol myristate acetate (PMA) and immunoglobulin G (IgG) and immunoglobulin E (IgE) immune complexes to stimulate hydrogen peroxide (H2O2) release from circulating eosinophils and neutrophils. PMA was able to stimulate a significant respiratory burst in both cell types, PMA-induced H2O2 production being higher in eosinophils than in neutrophils (p less than 0.05). Similar results were obtained when the cells were stimulated by IgG (p less than 0.05). In contrast, aggregated human myeloma IgE induced a detectable H2O2 release only from peripheral blood eosinophils. We conclude that H2O2 release from eosinophils may play a role in parenchymal injury associated with hypereosinophilic disorders and the presence of immune complexes at sites of disease activity.