Phagocytosis by Human Eosinophils

Eosinophils were isolated from the blood of patients with eosinophilia and tested for phagocytic ability. Eosinophils ingested inert polystyrene particles, Escherichia coli, Staphylococcus aureus 502A and Candida albicans, but did so less efficiently than neutrophils. They did not phagocytize antibody-coated red cells. Phagocytosis occurred over a broad pH range and in the presence of inhibitors of oxidative metabolism. Inhibitors of glycolysis, puromycin and colchicine inhibited particle ingestion to a variable extent.

Metabolic concomitants of phagocytosis, including enhanced incorporation of uridine into RNA, stimulation of glucose oxidation and degranulation and loss of lysosomal enzymes were similar in neutrophils and eosinophils. Endotoxin had similar effects on glucose oxidation by eosinophils and neutrophils in vitro.