Recruited macrophages control dissemination of group A Streptococcus from infected soft tissues.
J Immunol
; 187(11): 6022-31, 2011 Dec 01.
Article
en En
| MEDLINE
| ID: mdl-22025550
Group A Streptococcus (GAS) causes diverse infections in humans, ranging from mild to life-threatening invasive diseases, such as necrotizing fasciitis (NF), a rapidly progressing deep tissue infection. Despite prompt treatments, NF remains a significant cause of morbidity and mortality, even in previously healthy individuals. The early recruitment of leukocytes is crucial to the outcome of NF; however, although the role of polymorphonuclear neutrophils (PMNs) in host defense against NF is well established, the role of recruited macrophages remains poorly defined. Using a cutaneous murine model mimicking human NF, we found that mice deficient in TNF-α were highly susceptible to s.c. infections with GAS, and a paucity of macrophages, but not PMNs, was demonstrated. To test whether the effects of TNF-α on the outcome of infection are mediated by macrophages/monocytes, we systemically depleted C57BL/6 mice of monocytes by pharmacological and genetic approaches. Systemic monocyte depletion substantially increased bacterial dissemination from soft tissues without affecting the number of recruited PMNs or altering the bacterial loads in soft tissues. Enhanced GAS dissemination could be reverted by either i.v. injection of monocytes or s.c. administration of peritoneal macrophages. These experiments demonstrated that recruited macrophages play a key role in defense against the extracellular pathogen GAS by limiting its spread from soft tissues.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Infecciones Estreptocócicas
/
Fascitis Necrotizante
/
Macrófagos
Límite:
Animals
Idioma:
En
Revista:
J Immunol
Año:
2011
Tipo del documento:
Article
País de afiliación:
Israel
Pais de publicación:
Estados Unidos