• 1 January 1977
    • journal article
    • research article
    • Vol. 119 (5), 1584-1588
Abstract
Only 15-25% of purified oil-induced guinea pig macrophages could be lysed by treatment with anti-Ia [immune response-associated] antigen serum and C [complement]. Those cells remaining alive after treatment were not damaged and were metabolically active since they readily phagocytized latex beads. The Ia-negative macrophages were markedly deficient in their ability to present protein antigens to immune T [thymus-derived] lymphocytes and to function as stimulator cells when mixed with allogeneic T cells in the mixed leukocyte reaction. It appears that Ia antigens are expressed on a subpopulation of macrophages and that this subpopulation plays a critical role in the activation of T cell proliferation to soluble protein antigens and to alloantigens.