MACROPHAGE-LYMPHOCYTE INTERACTION .3. SITE OF ALLOANTISERUM INHIBITION OF T-LYMPHOCYTE PROLIFERATION INDUCED BY ALLOGENEIC OR ALDEHYDE-BEARING CELLS

Abstract

Inhibition by anti-Ia [immune response associated antigen] sera of guinea pig T [thymus-derived] lymphocyte proliferation induced by allogeneic macrophages (MLR [mixed leukocyte reactive macrophages]) and NaIO4 or neuraminidase-galactose oxidase-treated macrophages was investigated to identify the target cell upon which the antisera act. Anti-2 and anti-13 alloantisera inhibited MLR and aldehyde-induced T cell reactivity when directed against the specificity of the stimulatory macrophage. Little or no inhibition was observed when these antisera were directed against the T lymphocyte specificity when cultures were harvested at the time of peak proliferation. Anti-2 serum inhibited macrophage-lymphocyte rosette formation at 20 h between neuraminidase-galactose oxidase-treated strain 2 macrophages and strain 13 lymphocytes. Inhibition of T cell proliferation can be produced by anti-Ia sera directed against the macrophage. Ir gene products may function in part at the level of the macrophage.