M Protein Mediated Adhesion of M Type 24 Streptococcus Pyogenes Stimulates Release of interleukin-6 by HEp-2 Tissue Culture Cells

FEMS Microbiol Lett. 1997 Jun 1;151(1):65-70. doi: 10.1016/s0378-1097(97)00139-0.


We investigated the contributions of lipoteichoic acid and M protein to reversible and irreversible adhesion of group A streptococci and the effects of such adhesion on release of interleukin-6. Streptococci in which lipoteichoic acid was masked by the hyaluronate capsule were readily washed from HEp-2 cells, indicating no attachment. Unencapsulated, M-negative streptococci in which lipoteichoic acid was exposed were removed more slowly, indicating loose attachment. Only unencapsulated streptococci that expressed both lipoteichoic acid and M protein remained stably adherent to HEp-2 cells throughout multiple washes. Streptococci expressing both M protein and lipoteichoic acid induced release of interleukin-6 from HEp-2 cells, whereas an isogenic, M-negative mutant failed to induce release of interleukin-6. These data suggest that lipoteichoic acid mediates reversible adhesion and that M protein is required for irreversible adhesion and for inducing release of interleukin-6 from HEp-2 cells.

Publication types

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

MeSH terms

  • Antigens, Bacterial*
  • Bacterial Adhesion / immunology*
  • Bacterial Outer Membrane Proteins*
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Carrier Proteins*
  • Cell Survival
  • Cells, Cultured
  • Enzyme-Linked Immunosorbent Assay
  • Interleukin-6 / metabolism*
  • Liver / cytology
  • Liver / immunology*
  • Liver / microbiology
  • Mutation
  • Streptococcus pyogenes / genetics
  • Streptococcus pyogenes / pathogenicity*
  • Time Factors


  • Antigens, Bacterial
  • Bacterial Outer Membrane Proteins
  • Bacterial Proteins
  • Carrier Proteins
  • Interleukin-6
  • streptococcal M protein