Oxygen-derived radicals from Trypanosoma cruzi-stimulated human neutrophils.

This study provides biochemical and electron spin resonance spectroscopic evidence that contract of human polymorphonuclear leukocytes with antibody-coated Trypanosoma cruzi triggers the respiratory burst. Oxygen consumption, superoxide anion and hydrogen peroxide release were stimulated under conditions of polymorphonuclear leukocyte-mediated killing. This stimulation did not occur under non-killing conditions when antibody was omitted. A common mechanism of cytotoxicity of human polymorphonuclear leukocytes against different T. cruzi forms is suggested by the triggering of the respiratory burst by antibody-coated epimastigotes and trypomastigotes.