Human mononuclear subpopulations were tested for the capacity to produce interferon after mitogenic stimulation with protein A from Staphylococcus aureus. Mononuclear cells were separated into highly enriched macrophage, T-, B-, and null-cell subpopulations by Sephadex G-10 adherence, anti-human IgG F(ab′) two-column chromatography, and rosetting with sheep erythrocytes. Interferon (IFN) production was observed in both T- and null-cell preparations, but not in macrophage or B-cell preparations. Physicochemical and antigenic characterization of IFN from T- and null-cell preparations showed that both mononuclear subpopulations produced gamma IFN (IFNγ). Regulatory studies showed that IFNγ production was differentially regulated by macrophages. Macrophage addition to T lymphocytes augmented both cellular proliferation and IFNγ production, whereas macrophage addition to null cells suppressed IFNγ production and had no effect on the minimal proliferative response observed for these cells.
ASJC Scopus subject areas