Regulation of timothy grass pollen IgE antibody formation. I. In-vitro induction of suppressor T cells by soluble T suppressor factors.

A method using mini-Marbrook chambers in culturing normal spleen cells with timothy-specific T suppressor factor TSF and second order T suppressor factor TSF2 to induce suppressor T (TS) cells is described. Spleen cells cultured with T suppressor factors injected intravenously into recipients primed 20 days earlier with antigen and boosted with antigen within 24 hr of cell transfer, significantly suppress a secondary anti-antigen-B (AgB)-IgE response. On the other hand, spleen cells cultured with normal rabbit IgG failed to suppress the secondary anti-AgB-IgE response in recipient mice. The failure of enriched T cells cultured with either TSF or TSF2 to produce TS cells suggest that an accessory cell may be important in 'presentation' of these soluble factors during the induction of TS cells.