A new pathway of staphylococcal pathogenesis: apoptosis-like death induced by Staphopain B in human neutrophils and monocytes.
J Innate Immun
; 1(2): 98-108, 2009.
Article
en En
| MEDLINE
| ID: mdl-20375568
ABSTRACT
Circulating neutrophils and monocytes form the first line of cellular defense against invading bacteria. Here, we describe a novel and specific mechanism of disabling and eliminating phagocytes by Staphylococcus aureus. Staphopain B (SspB) selectively cleaved CD11b on phagocytes, which rapidly acquired features of cell death. SspB-treated phagocytes expressed phosphatidylserine as well as annexin I and became permeable to propidium iodide, thus demonstrating distinctive features of both apoptosis and necrosis, respectively. The cell death observed was caspase and Syk tyrosine kinase independent, whilst cytochalasin D efficiently inhibited the staphopain-induced neutrophil killing. Neutrophil and monocyte cell death was not affected by integrin clustering ligands (ICAM-1 or fibrin) and was prevented, and even reversed, by IgG. This protective effect was dependent on the Fc fragment, collectively suggesting cooperation of the CD16 receptor and integrin Mac-1 (CD11b/CD18). We conclude that SspB, particularly in the presence of staphylococcal protein A, may reduce the number of functional phagocytes at infection sites, thus facilitating colonization and dissemination of S. aureus.
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Infecciones Estafilocócicas
/
Staphylococcus aureus
/
Cisteína Endopeptidasas
/
Monocitos
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Apoptosis
/
Neutrófilos
Tipo de estudio:
Etiology_studies
Límite:
Humans
Idioma:
En
Revista:
J Innate Immun
Asunto de la revista:
ALERGIA E IMUNOLOGIA
Año:
2009
Tipo del documento:
Article
País de afiliación:
Polonia