Production of migration inhibition factor (MIF) by purified human T cell subpopulations

Abstract

T cells possessing suppressor activity (TG) were isolated from normal human peripheral blood by rosetting with IgG-coated ox red blood cells (OxRBC) as shown by their ability to inhibit pokeweed mitogen (PWM) induced proliferation and Ig synthesis in vitro. The suppressor activity of the intact T cell and Tg cell fractions was enhanced by concanavalin A (Con A) stimulation for 48 hr and supernatants from these Con A-treated cell cultures, after removal of mitogen, contained migration inhibition factor (MIF). Its release appeared to be primarily a function of the TG cells. The bulk of the MIF activity was present in a gel filtration fraction of mol. wt approx. 25,000, similar to that found in previous studies of Con A- or antigen-induced MIF in man.