title: Streptococcal M protein extracted by nonionic detergent. II. Analysis of the antibody response to the multiple antigenic determinants of the M-protein molecule.
abstract: Purified streptococcal M protein extracted by nonionic detergent was used in an RIA and a solid-phase radiocompetitive inhibition assay to determine the nature of the immune response in both human beings and hyperimmunized rabbits to this complex antiphagocytic antigen. Results indicate that a type-specific response to an M antigen with the development of opsonic antibodies is the result of antibodies directed against the majority of the antigenic determinants of the molecule. Cross-reactions between certain M types on the other hand, are represented by antibodies directed against only a small percentage of these antigenic determinants. Results also suggest that avidity may play a role in the action of opsonic antibodies. However, the data indicate that factors besides avidity (i.e. sites bound by the antibodies) also seem essential for opsonization.
mesh_terms: D000328:Adult; D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis / Q000096:biosynthesis*; D000917:Antibody Formation; D000918:Antibody Specificity; D000936:Antigen-Antibody Complex; D000942:Antigens, Bacterial / Q000302:isolation & purification*; D001426:Bacterial Proteins / Q000276:immunology; D001666:Binding Sites, Antibody; D002648:Child; D002675:Child, Preschool; D003429:Cross Reactions; D000939:Epitopes; D006801:Humans; D009895:Opsonin Proteins / Q000032:analysis / Q000096:biosynthesis*; D011817:Rabbits; D013297:Streptococcus pyogenes / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D000936:Antigen-Antibody Complex; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D000939:Epitopes; D009895:Opsonin Proteins