Effect of human leukocyte interferon on phagocytic activity of polymorphonuclear leukocytes.

The effect of homologous leukocyte interferon HuIFN on the phagocytic activity of human polymorphonuclear (PMN) leukocytes was examined. The PMN cells were obtained from healthy donors and they were grown on coverslips. Escherichia coli labelled with 32P-orthophosphate was phagocytized in the presence of fresh homologous serum during a 15 min incubation period. PMN cells pretreated with interferon for at least 3 hours ingested more bacteria as compared to untreated controls. This effect was dose dependent, in maximal effect being obtained with 10(3) units per ml. The effect was species specific and it was neutralized by antiinterferon globulin.