EFFECT OF 17-BETA-ESTRADIOL ON EXPRESSION OF IL-2, IL-6 AND IFN-GAMMAMESSENGER-RNA IN HUMAN TONSILLAR CELLS

Oestradiol (E(2)) alters lymphocyte function in vitro including T cell DNA synthesis and B cell immunoglobulin production in human tonsillar , splenic and peripheral blood cells. We have investigated whether one mechanism for this effect is that E(2) modifies the expression of IL- 2, IL-6 and IFN-gamma mRNA in human tonsillar mononuclear cells. Witho ut E(2), addition of PHA (1 mu g ml(-1)) for 10 h increased the expres sion of IL-2 and IL-6 mRNA but had no significant effect on IFN-gamma mRNA. In separated T cells after 24 h incubation, E(2) (7 X 10(-8) M) increased only the IFN-gamma mRNA levels. However, when E(2) was prese nt in PHA-stimulated T cell cultures, mRNA levels from all cytokines w ere suppressed. E(2) decreased IL-2 mRNA levels in the T cell preparat ion after 24 h culture. For IL-6, E(2) decreased mRNA both in mononucl ear cells and T cells after 10 h incubation. For IFN-gamma, E(2) decre ased mRNA levels in the mononuclear cell preparation after 24 h cultur e. Stimulation of the T cell preparation with PHA after 24 h incubatio n with E(2) decreased the IFN-gamma mRNA levels compared to the cultur es incubated with E(2) only. One part of the action of E(2) may be thr ough a block in the up-regulation of the mRNA of IL-2, IL-6 and IFN-ga mma in activated cells.