title: Biological expressions of lymphocyte activation. II. Generation of a population of thymus-derived suppressor lymphocytes.
abstract: A population of thymus-derived lymphocytes has been identified that, upon activation by the nonspecific plant mitogen concanavalin A, suppresses the development of plaque-forming cell responses in fresh or 48-h antigen-stimulated cultures of mouse spleen cells. Suppressor cells can inhibit both primary and secondary IgM and IgG responses in vitro. X-irradiation before activation of peripheral thymus-derived cells by concanavalin A abrogates generation of suppressor cells. After a 48 h activation period, however, the function of concanavalin A-activated suppressor cells is radioresistant. As yet uncertain is whether these suppressor cells are a population of cells distinct from thymus-derived "helper" cells. In certain important regards, the cells mediating these two opposing functions share similar characteristics; the effect observed may be determined by the circumstances of activation or the numbers of activated cells, and may consequently represent different functions of a single thymus-derived regulator cell population.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D000921:Antibody-Producing Cells; D002452:Cell Count; D002470:Cell Survival; D002478:Cells, Cultured; D003165:Complement System Proteins; D003208:Concanavalin A / Q000494:pharmacology; D006462:Hemolytic Plaque Technique; D007106:Immune Sera / Q000494:pharmacology; D007074:Immunoglobulin G / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D007165:Immunosuppression Therapy; D037102:Lectins / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D011830:Radiation Effects; D013154:Spleen; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000528:radiation effects; D013997:Time Factors
chemical_list: D007106:Immune Sera; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D037102:Lectins; D003208:Concanavalin A; D003165:Complement System Proteins