Effect of EGTA on phagocytosis of Salmonella typhimurium by human neutrophils.

The ingestion of mutant strains of Salmonella typhimurium by human neutrophils was greatly reduced by the presence of ethylene glycol tetra-acetic acid (EGTA) in the reaction mixture. Ingestion of preopsonized bacteria by neutrophils was little affected by Ca++ in the reaction mixture but largely reduced by the presence of EGTA. In addition to chelation of Ca++, EGTA has an adverse effect on neutrophils. In studies of phagocytosis, to avoid this effect, EGTA should not be present in the reaction mixture when it is used to prevent the complement classical pathway activation.