A role for C5 and C5a-ase in the acute neutrophil response to group B streptococcal infections.

Abstract

Congenic C5-deficient and C5-sufficient mice were infected with group B streptococci (GBS) to determine if the polymorphonuclear leukocyte (PMNL) chemoattractant C5a contributes to PMNL recruitment in GBS infection and if GBS C5a-ase reduces C5a-induced PMNL recruitment in vivo. PMNL accumulation was greater in the peritoneum and air spaces of C5-sufficient mice than in C5-deficient mice. Administration of human C5 to C5-deficient mice caused a significant increase in PMNL recruitment following infection with C5a-ase-negative GBS. GBS C5a-ase did not reduce PMNL accumulation in C5-sufficient mice but reduced PMNL recruitment in C5-deficient mice reconstituted with human C5. These data indicate that C5a is important for rapid PMNL recruitment to sites of GBS infection and that GBS C5a-ase inactivates human, but not murine, C5a in vivo. Reduction of the acute inflammatory response by C5a-ase likely contributes to GBS virulence in human neonates.

• Authors: J F Bohnsack, K Widjaja, S Ghazizadeh, C E Rubens, D R Hillyard, C J Parker, K H Albertine, H R Hill
• Journal: The Journal of infectious diseases (J Infect Dis) Vol. 175 Issue 4 Pg. 847-55 (Apr 1997) ISSN: 0022-1899 [Print] United States
• PMID: 9086140 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Adhesins, Bacterial
• Complement C5
• Complement Inactivator Proteins
• Endopeptidases
• C5a peptidase

Topics

• Adhesins, Bacterial
• Animals
• Complement C5 (physiology)
• Complement Inactivator Proteins (physiology)
• Endopeptidases (physiology)
• Humans
• Male
• Mice
• Neutrophils (immunology)
• Streptococcal Infections (immunology)
• Streptococcus agalactiae (immunology)