Impact of immunization against SpyCEP during invasive disease with two streptococcal species: Streptococcus pyogenes and Streptococcus equi

Vaccine. 2009 Aug 6;27(36):4923-9. doi: 10.1016/j.vaccine.2009.06.042. Epub 2009 Jun 27.


Currently there is no licensed vaccine against the human pathogen Streptococcus pyogenes. The highly conserved IL-8 cleaving S. pyogenes cell envelope proteinase SpyCEP is surface expressed and is a potential vaccine candidate. A recombinant N-terminal part of SpyCEP (CEP) was expressed and purified. AntiCEP antibodies were found to neutralize the IL-8 cleaving activity of SpyCEP. CEP-immunized mice had reduced bacterial dissemination from focal S. pyogenes intramuscular infection and intranasal infection. We also identified a functional SpyCEP-homolog protease SeCEP, expressed by the equine pathogen Streptococcus equi, which was able to cleave both human and equine IL-8. CEP-immunized mice also demonstrated reduced bacterial dissemination from S. equi intramuscular infection. Therefore immunization against SpyCEP may provide protection against other streptococci species with homologous proteases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies, Bacterial / immunology
  • Antigens, Bacterial / immunology*
  • Colony Count, Microbial
  • Liver / microbiology
  • Mice
  • Molecular Sequence Data
  • Neutralization Tests
  • Peptide Hydrolases / immunology*
  • Sequence Alignment
  • Spleen / microbiology
  • Streptococcal Infections / prevention & control*
  • Streptococcal Infections / therapy*
  • Streptococcal Vaccines / immunology*
  • Streptococcus equi / immunology*
  • Streptococcus pyogenes / immunology*
  • Vaccines, Synthetic / immunology


  • Antibodies, Bacterial
  • Antigens, Bacterial
  • Streptococcal Vaccines
  • Vaccines, Synthetic
  • Peptide Hydrolases
  • SpyCEP protein, Streptococcus pyogenes