title: Synergistic effects of antigen and soluble T-cell factors in B-lymphocyte activation.
abstract: Supernatants from phorbol 12-myristate 13-acetate-activated cultures of the mouse EL4 thymoma, or of several mouse T-cell hybridomas stimulated either by their specific antigen or by concanavalin A, induced primary splenic B cells to proliferate and differentiate to antibody-secreting cells. This effect was not due to interleukin 2 and did not require the presence of macrophages. The antibody response was polyclonal, including antibodies specific for 2,4-dinitrophenyl and pigeon cytochrome c, present in amounts of 1% or less of the total immunoglobulin produced. The addition of either of these antigens increased the amount of the corresponding specific antibody. At very high concentrations of dinitrophenyl-hemocyanin the specific response could be depressed. These observations were taken to demonstrate that soluble T-cell factors are sufficient to activate a portion of naive B cells to antibody secretion and that under these conditions in vitro the presence of antigen merely enhances the specific response.
mesh_terms: D019297:2,4-Dinitrophenol; D000818:Animals; D000917:Antibody Formation; D000941:Antigens / Q000276:immunology*; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D002455:Cell Division; D002478:Cells, Cultured; D003574:Cytochrome c Group; D004140:Dinitrophenols; D004357:Drug Synergism; D005260:Female; D007376:Interleukin-2 / Q000276:immunology*; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D008808:Mice, Inbred CBA; D013945:Thymoma / Q000276:immunology; D013953:Thymus Neoplasms / Q000276:immunology
chemical_list: D000941:Antigens; D003574:Cytochrome c Group; D004140:Dinitrophenols; D007376:Interleukin-2; D019297:2,4-Dinitrophenol