A New Heart-Cross-Reactive Antigen in Streptococcus Pyogenes Is Not M Protein

J Infect Dis. 1990 Oct;162(4):875-82. doi: 10.1093/infdis/162.4.875.


To identify tissue-cross-reactive antigens other than M protein in Streptococcus pyogenes, proteins of M-positive strains and an M-negative strain were probed in Western blots for reactivity with cross-reactive streptococcal monoclonal antibodies (MAbs) 36.2.2 and 54.2.8. A protein(s) near a molecular mass of 60 kDa in extracts of five group A streptococcal serotypes and the M-negative strain reacted with the MAbs. A study of human antibody responses to purified membranes of S. pyogenes indicated a hyperreactivity to a 60-kDa protein in acute rheumatic fever. Since MAbs 36.2.2 and 54.2.8 are known to cross-react with myosin or actin and streptococcal M protein, the data suggest that a homology or conformation is shared between the 60-kDa antigen and M protein. Therefore, the 60-kDa antigen is a new heart- or tissue-cross-reactive antigen of S. pyogenes that shares immunologic epitopes with but is distinct from M protein.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acute Disease
  • Antibodies, Bacterial / biosynthesis
  • Antibodies, Monoclonal / immunology
  • Antigens, Bacterial / immunology*
  • Bacterial Outer Membrane Proteins*
  • Bacterial Proteins / immunology*
  • Blotting, Western
  • Carrier Proteins*
  • Cell Wall / immunology
  • Cross Reactions
  • Enzyme-Linked Immunosorbent Assay
  • Epitopes / immunology
  • Humans
  • Myocardium / immunology
  • Rheumatic Fever / etiology
  • Rheumatic Fever / immunology*
  • Streptococcal Infections / complications
  • Streptococcal Infections / immunology*
  • Streptococcus pyogenes / immunology*


  • Antibodies, Bacterial
  • Antibodies, Monoclonal
  • Antigens, Bacterial
  • Bacterial Outer Membrane Proteins
  • Bacterial Proteins
  • Carrier Proteins
  • Epitopes
  • streptococcal M protein