Antigen-binding T cells of mice immunized with low doses of syngenic spleen cells modified by 2,4,6-trinitrophenyl sulphonic acid, were fused with BW 5147.3.13 thymoma subclone. Suppressor hybridomas were not identical in their differentiating antigens and functional activity. Extract from Lyt 1-2+ hybridoma suppressed efferent and afferent limbs of delayed type hypersensitivity (DTH) in recipients sensitized with subcutaneous injection of 3 X 10(7) TNP-SC. Extract from Lyt 1+2+ I-hybridoma suppressed only afferent DTH limb. It is suggested that during DTH induction with low doses of hapten-modified cells the generation of different types of antigen-binding DTH T suppressors takes place.