Effect of stimulation and blockade of mononuclear phagocyte system on the induction of suppressor T cells of delayed footpad reaction to SRBC in mice.

The role of mononuclear phagocyte system (MPS) in the induction of suppressor T cells which depress the delayed footpad reaction to sheep erythrocytes (SR BC) was studied in mice in which MPS was blocked or stimulated. Colloidal carbon and diethyl- stilbestrol were used for blockade and stimulation respectively. Adoptive transfer of suppressor T cells was achieved by spleen cells of mice immunized intra- peritoneally with varying doses of SRBC. In non-treated mice, 1 × 10⁹ SRBC were required to induce suppressor T cells, while 6 × 10⁸ could not induce the suppressor T cells. In MPS-blocked mice, however, even 6 × 10⁸ SRBC could induce the suppressor T cells. On the other hand, 3 × 10⁸ SRBC were required for the induction of suppressor T cells in MPS-stimulated mice. These results suggest that the activity of macrophages as scavenger cells modulates the subsequent induction of suppressor T cells after immunization with high doses of SRBC. [ABSTRACT FROM AUTHOR]