title: M protein mediated adhesion of M type 24 Streptococcus pyogenes stimulates release of interleukin-6 by HEp-2 tissue culture cells.
abstract: 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.
authors.affiliation: Veterans Affairs Medical Center, University of Tennessee, Memphis, USA. hcourtney@utmem1.utmem.edu
authors.forename: H S
authors.initials: HS
authors.lastname: Courtney
authors.forename: I
authors.initials: I
authors.lastname: Ofek
authors.forename: D L
authors.initials: DL
authors.lastname: Hasty
mesh_terms: D000942:Antigens, Bacterial; D001422:Bacterial Adhesion / Q000276:immunology*; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002352:Carrier Proteins; D002470:Cell Survival; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D015850:Interleukin-6 / Q000378:metabolism*; D008099:Liver / Q000166:cytology / Q000276:immunology* / Q000382:microbiology; D009154:Mutation; D013297:Streptococcus pyogenes / Q000235:genetics / Q000472:pathogenicity*; D013997:Time Factors
chemical_list: D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D015850:Interleukin-6; C014689:streptococcal M protein