Antibacterial activity of the contact and complement systems is blocked by SIC, a protein secreted by Streptococcus pyogenes.
Författare
Summary, in English
Recent studies have shown that activation of the complement and contact systems results in the generation of antibacterial peptides. Streptococcus pyogenes, a major bacterial pathogen in humans, exists in more than one hundred different serotypes due to sequence variation in the surface-associated M protein. Cases of invasive and life-threatening S. pyogenes infections are commonly associated with isolates of the M1 serotype, and in contrast to the large majority of M serotypes, M1 isolates all secrete the SIC protein. Here we show that SIC interferes with the activation of the contact system, and blocks the activity of antibacterial peptides generated through complement and contact activation. This effect promotes the growth of S. pyogenes in human plasma, and in a mouse model of S. pyogenes sepsis, SIC enhances bacterial dissemination, results which help to explain the high frequency of severe S. pyogenes infections caused by isolates of the M1 serotype.
Avdelning/ar
Publiceringsår
2011
Språk
Engelska
Sidor
1331-1340
Publikation/Tidskrift/Serie
Journal of Biological Chemistry
Volym
286
Fulltext
Länkar
Dokumenttyp
Artikel i tidskrift
Förlag
American Society for Biochemistry and Molecular Biology
Ämne
- Dermatology and Venereal Diseases
- Infectious Medicine
Status
Published
Forskningsgrupp
- Immunomodulatory effects of platelets during inflammation and infection
- Infection and immunomodulation
ISBN/ISSN/Övrigt
- ISSN: 1083-351X