title: Selective effect of irradiation on responses to thymus-independent antigen.
abstract: Low doses of ionizing radiation have a selective immunosuppressive effect on in vivo B cell responses to thymus-independent (TI) antigens. The B cell response, assayed as direct anti-trinitrophenyl (TNP)-specific plaque-forming cells (PFC), induced by type 2, TI antigens (TNP-Ficoll or TNP-Dextran), was reduced, on the average, by 10-fold in animals exposed to 200 rad of ionizing radiation 24 hr before antigen challenge. In contrast, PFC responses to type 1, TI antigens (TNP-lipopolysaccharide or TNP-Brucella abortus) are unaffected in mice exposed to the same dose of radiation. Adoptive transfers showed that this selective immunosuppression is a result of the specific inactivation of the B cell subpopulation responding to type 2, TI antigens. These experiments suggest that physiologic differences exist in the B cell subpopulations of normal mice which respond to type 1, or type 2, TI antigens.
mesh_terms: D000818:Animals; D000921:Antibody-Producing Cells / Q000528:radiation effects*; D000955:Antigens, T-Independent / Q000008:administration & dosage* / Q000528:radiation effects; D001402:B-Lymphocytes / Q000276:immunology / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005362:Ficoll / Q000008:administration & dosage / Q000031:analogs & derivatives; D006462:Hemolytic Plaque Technique; D007165:Immunosuppression Therapy / Q000379:methods; D008070:Lipopolysaccharides / Q000494:pharmacology; D008213:Lymphocyte Activation / Q000528:radiation effects; D008297:Male; D051379:Mice; D008805:Mice, Inbred A; D008807:Mice, Inbred BALB C; D008808:Mice, Inbred CBA; D014301:Trinitrobenzenes / Q000008:administration & dosage
chemical_list: D000955:Antigens, T-Independent; D008070:Lipopolysaccharides; C020529:TNP-ficoll; D014301:Trinitrobenzenes; D005362:Ficoll