Production of human interferon-gamma in serum-free medium

Interferon (IFN)-gamma was produced with a high yield in cultures of human peripheral mononuclear cells by combined stimulation with OK-432 and staphylococcal enterotoxin B. Human mononuclear cells cultured in serum-free medium produced several times as much IFN as those in RPMI-1640 medium containing 10% fetal bovine serum. A synergistic effect of OK-432 and staphylococcal enterotoxin B on the production of IFN-gamma was demonstrated. Ultrogel AcA54 column chromatography of crude IFN showed a single peak with an apparent molecular weight of 43,000. Our production system for human IFN-gamma offers a feasible approach to preparation of large quantities of purified IFN-gamma for structure studies, antibody production, and clinical applications.