Staphylococcal complement evasion by various convertase-blocking molecules.
J Exp Med
; 204(10): 2461-71, 2007 Oct 01.
Article
em En
| MEDLINE
| ID: mdl-17893203
ABSTRACT
To combat the human immune response, bacteria should be able to divert the effectiveness of the complement system. We identify four potent complement inhibitors in Staphylococcus aureus that are part of a new immune evasion cluster. Two are homologues of the C3 convertase modulator staphylococcal complement inhibitor (SCIN) and function in a similar way as SCIN. Extracellular fibrinogen-binding protein (Efb) and its homologue extracellular complement-binding protein (Ecb) are identified as potent complement evasion molecules, and their inhibitory mechanism was pinpointed to blocking C3b-containing convertases the alternative pathway C3 convertase C3bBb and the C5 convertases C4b2aC3b and C3b2Bb. The potency of Efb and Ecb to block C5 convertase activity was demonstrated by their ability to block C5a generation and C5a-mediated neutrophil activation in vitro. Further, Ecb blocks C5a-dependent neutrophil recruitment into the peritoneal cavity in a mouse model of immune complex peritonitis. The strong antiinflammatory properties of these novel S. aureus-derived convertase inhibitors make these compounds interesting drug candidates for complement-mediated diseases.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Staphylococcus aureus
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Proteínas de Bactérias
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Proteínas do Sistema Complemento
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Fatores de Virulência
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Convertases de Complemento C3-C5
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Ano de publicação:
2007
Tipo de documento:
Article