Virulence mechanism of bacteria in mixed infection: attenuation of cytokine levels and evasion of polymorphonuclear leukocyte phagocytosis.
J Periodontol
; 84(10): 1463-8, 2013 Oct.
Article
em En
| MEDLINE
| ID: mdl-23259412
ABSTRACT
BACKGROUND:
The objective of the present study is to evaluate the effect of bacterial viability on the virulence of mixed infection.METHODS:
Expression of pro- and anti-inflammatory cytokines (interleukin [IL]-1ß and IL-10, respectively) was tested in vivo, following live versus heat-killed infection (mono or mixed), using the mouse chamber model of infection. Ex vivo, phagocytosis of fluorescently labeled bacteria was tested in primary mouse polymorphonuclear leukocytes by flow cytometry.RESULTS:
In monoinfection, heat-killed Porphyromonas gingivalis led to augmented levels of IL-1ß 2 hours postinfection, whereas IL-10 levels remained unaffected. Phagocytosis of heat-killed P. gingivalis was reduced compared with that of the live P. gingivalis, whereas phagocytosis of heat-killed Fusobacterium nucleatum was augmented compared with that of live F. nucleatum. In mixed infection, both IL-1ß and IL-10 levels were augmented 24 hours postinfection when the bacteria were heat-killed. Although the phagocytosis pattern of F. nucleatum in the mixed infection remained similar to that upon monoinfection, phagocytosis of P. gingivalis was reduced following mixed infection.CONCLUSIONS:
The inflammatory response to live mixed infection is attenuated with reduced phagocytosis, compared with that of heat-killed mixed infection. The lower response to live mixed infection could stem from a mechanism enabling the bacteria to evade the host response, thereby increasing bacterial survival.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fagocitose
/
Interleucinas
/
Fusobacterium nucleatum
/
Infecções por Bacteroidaceae
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Porphyromonas gingivalis
/
Coinfecção
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Infecções por Fusobacterium
/
Neutrófilos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
J Periodontol
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Israel