title: Idiotypes of pre-existing human anti-carcinoma anti-T and anti-Tn antibodies.
abstract: All humans normally possess antibodies, predominantly IgM, that react specifically with the Thomsen-Friedenreich (T) and the Tn antigens which are present in immunoreactive form on > 85% of all human carcinomas, but not in healthy and otherwise diseased tissues. We report here a serological study of idiotype expression and antigen reactivity of the anti-T and anti-Tn antibodies. Idiotypy was analyzed with rabbit antibodies raised against, and made specific for, affinity-purified polyclonal anti-T and anti-Tn antibodies from blood group A1B healthy adult donors. Anti-T and anti-Tn antibodies cross-reacted idiotypically in spite of their distinct epitope specificities. By adsorbing anti-T antibodies on insolubilized synthetic T carbohydrate we could firmly link idiotype expression with antigen reactivity. The relation of idiotype expression to the antigen-binding site of plant seed lectins was also studied; one originated from Arachis hypogaea [peanut agglutinin (PNA)], the other from Artocarpus integrifolia (Jacalin). PNA inhibited only anti-T antibodies. Jacalin inhibited both anti-T and anti-Tn antibodies in a dose-dependent manner. Neither idiotypic nor anti-idiotypic antibodies diminished the binding of lectins to T and Tn epitopes. The shared idiotypes on natural anti-T and anti-Tn antibodies permit consideration of application of their anti-idiotypes in treatment and/or prevention of human carcinoma.
authors.affiliation: Department of Medicine, University of California, San Diego 92103.
authors.forename: M
authors.initials: M
authors.lastname: Zanetti
authors.forename: G
authors.initials: G
authors.lastname: Lenert
authors.forename: G F
authors.initials: GF
authors.lastname: Springer
mesh_terms: D000328:Adult; D000818:Animals; D000912:Antibodies, Neoplasm / Q000276:immunology*; D000951:Antigens, Neoplasm / Q000276:immunology* / Q000378:metabolism; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000276:immunology*; D014408:Biomarkers, Tumor / Q000276:immunology; D002240:Carbohydrate Sequence; D003429:Cross Reactions; D000939:Epitopes / Q000276:immunology; D005260:Female; D006801:Humans; D007113:Immunity, Innate; D007130:Immunoglobulin Idiotypes / Q000276:immunology*; D037102:Lectins / Q000378:metabolism; D008969:Molecular Sequence Data; D019887:Peanut Agglutinin; D037121:Plant Lectins; D011817:Rabbits
chemical_list: D000912:Antibodies, Neoplasm; D000951:Antigens, Neoplasm; D015295:Antigens, Tumor-Associated, Carbohydrate; D014408:Biomarkers, Tumor; D000939:Epitopes; D007130:Immunoglobulin Idiotypes; D037102:Lectins; D019887:Peanut Agglutinin; D037121:Plant Lectins; C040286:Tn antigen; C043696:jacalin; C016467:Thomsen-Friedenreich antigen