title: Cross-reactions between pneumococci and other streptococci due to C polysaccharide and F antigen.
abstract: By serological methods, all 83 known types of Streptococcus pneumoniae could be shown to possess C polysaccharide and F antigen. Cross-reactions due to these two antigens between pneumococci and a broad range of most other commonly encountered streptococci were examined. The presence of an antigen closely similar or identical to pneumococcal C polysaccharide was demonstrated in some strains of Streptococcus mitior. Therefore, we conclude that pneumococci cannot be identified serologically from mixed samples without culture. Streptococcal group C antiserum was found to cross-react with pneumococcal F antigen.
mesh_terms: D000942:Antigens, Bacterial / Q000276:immunology*; D015478:Antigens, Heterophile / Q000276:immunology*; D003429:Cross Reactions; D005577:Forssman Antigen / Q000276:immunology*; D007122:Immunoelectrophoresis; D007123:Immunoelectrophoresis, Two-Dimensional; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D013291:Streptococcus / Q000276:immunology*; D013296:Streptococcus pneumoniae / Q000276:immunology*
chemical_list: D000942:Antigens, Bacterial; D015478:Antigens, Heterophile; D011135:Polysaccharides, Bacterial; C027158:polysaccharide C-substance (Streptococcus); D005577:Forssman Antigen