title: Induction of human antigen-specific suppressor factors in vitro.
abstract: Based on methods used for the in vitro induction of antigen-specific suppressor cells in the mouse, we have cultured Ficoll-Isopaque-separated human blood cells with high dose of antigen (100 microgram/ml) in Marbrook culture vessels for 4 days. The resulting cells, when further recultured for 24 hr with a low dose of antigen (1 microgram/ml), released into the supernatant material, termed 'suppressor factor', which inhibited, in an antigen-specific manner, the antibody response of mouse spleen cells in culture. The suppressor factor was analysed using immunoabsorbents, and was bound to and eluted from specific antigen, concanavalin A and lentil lectin, anti-human Ia antibodies, and anti-mouse suppressor factor antibodies, but was not bound to antibodies against human IgG.
mesh_terms: D000941:Antigens / Q000276:immunology; D046508:Culture Techniques; D000939:Epitopes / Q000276:immunology*; D006801:Humans; D007106:Immune Sera; D007136:Immunoglobulins / Q000096:biosynthesis; D007163:Immunosorbent Techniques; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D000941:Antigens; D000939:Epitopes; D007106:Immune Sera; D007136:Immunoglobulins