title: Immunogenic properties of modified antigen E. III. Effect of repeated injections of modified antigen on immunocompetent cells specific for native antigen.
abstract: It has been shown that ragweed antigen E loses its major antigenic determinants after denaturation in 8 M urea, but urea-denatured (UD) antigen and an alpha-polypeptide chain isolated from the denatured molecules are capable of priming mouse T cells specific for native antigen. Weekly injections of 10mug UD antigen or alpha-chain into antigen E-primed animals depressed the ongoing IgE antibody response, whereas injections of the same dose of antigen E failed to depress the antibody response. It was found by adoptive transfer experiments that helper activity of antigen E-primed splenic T cells was depressed by the treatment of the donors with either modified antigen or native antigen E. The same treatment of antigen E-primed animals depressed the DNA synthetic response of their splenic T cells to antigen E. The treatment of antigen E-primed animals with UD antigen resulted in a decrease of antigen E-specific IgE-B cells and IgG-B cells in their spleen, whereas the treatment with native antigen expanded the B cell populations. In view of the results obtained in the mouse, cellular basis for the immunologic effects of hyposensitization treatment is discussed.
mesh_terms: D000818:Animals; D000906:Antibodies; D000917:Antibody Formation; D000941:Antigens / Q000008:administration & dosage / Q000032:analysis*; D000961:Antilymphocyte Serum / Q000494:pharmacology; D001402:B-Lymphocytes / Q000276:immunology; D003165:Complement System Proteins; D000939:Epitopes; D005260:Female; D007073:Immunoglobulin E; D007074:Immunoglobulin G; D051379:Mice; D008805:Mice, Inbred A; D010323:Passive Cutaneous Anaphylaxis; D010455:Peptides / Q000008:administration & dosage; D006109:Poaceae / Q000276:immunology*; D051381:Rats; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology; D014508:Urea / Q000378:metabolism
chemical_list: D000906:Antibodies; D000941:Antigens; D000961:Antilymphocyte Serum; D000939:Epitopes; D007074:Immunoglobulin G; D010455:Peptides; D007073:Immunoglobulin E; D014508:Urea; D003165:Complement System Proteins