Superoxide anion-generating activities of macrophages as studied by using cytochalasin E and lectins as synergistic stimulants for superoxide release.

Treatment of macrophages with cytochalasin E in combination with a lectin was found to stimulate the generation of superoxide anions (O2-) very efficiently. The macrophages stimulated with concanavalin A, phytohemagglutinin or wheat germ agglutinin released superoxide, but cells pretreated with cytochalasin E released much greater amounts of superoxide, without notable lag time, upon stimulation with the lectin. Wheat germ agglutinin was found to be the most efficient stimulant among the lectins tested. Superoxide generation in guinea pig macrophages was shown to be dependent largely on cytoplasmic glucose metabolism and to some extent on mitochondrial respiration, since the superoxide release was largely but not totally inhibited by 2-deoxyglucose and to a lesser extent by antimycin A or KCN. The method presented is sensitive and allows rapid assay of the superoxide-generating activity with only 1--5 X 10(5) macrophages for a single determination. In application of this technique, elevation of the superoxide-generating activity was shown with macrophages elicited by chemical inflammation or those obtained from mice after treatment with tubercle bacilli.