title: Immunoregulatory circuits among T cell sets: effect of mode of immunization on determining which Lyl T cell sets will be activated.
abstract: Lyl T cells are able to induce B cells to make antibody and also to induce a resting Lyl23 T cell set to exert potent feedback suppression. Which of these two pathways Lyl T cells take can be influenced by the mode of immunization. In particular, in vitro immunized Lyl T cells are more likely to induce suppression than are Lyl T cells immunized in vivo even when both populations deliver the same amount of help to purified B cells. The feedback suppression induced by the Lyl T cells immunized in vitro can be distinguished from suppression mediated by Ly2+ T cells; in the former case suppression is preceded by a precocious antibody response, whereas suppression mediated by Ly2+ T cells is apparent throughout the entire period of observation.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000276:immunology; D002469:Cell Separation; D006462:Hemolytic Plaque Technique; D007114:Immunization; D007074:Immunoglobulin G; D007165:Immunosuppression Therapy; D051379:Mice; D008810:Mice, Inbred C57BL; D012756:Sheep; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D007074:Immunoglobulin G