STAT6 signalling is important in CD8 T-cell activation and defence against Toxoplasma gondii infection in the brain.
Immunology
; 127(2): 187-95, 2009 Jun.
Article
em En
| MEDLINE
| ID: mdl-18795973
ABSTRACT
Signal transducer and activator of transcription (STAT) 6 is a molecule involved in interleukin (IL)-4 and -13 signalling. We investigated the role of STAT6 signalling in Toxoplasma gondii-infected mice using STAT6-deficient (STAT6(-/-)) and wild-type (WT) mice. A significantly larger number of cysts were recovered from the brain in STAT6(-/-) than in WT mice on days 28 and 56 post-infection. CD8(+) T cells in cerebrospinal fluid and spleen stimulated with T. gondii antigen produced higher levels of interferon (IFN)-gamma in WT than in STAT6(-/-) mice. CD8(+) T-cell function, estimated by expression of CD25 and cytotoxic activity, was lower in STAT6(-/-) than in WT mice. Transfer of CD8(+) but not CD4(+) T cells, purified from infected WT mice, into STAT6(-/-) mice successfully prevented formation of cysts in the brain. However, transfer of naïve CD8(+) T cells from WT into STAT6(-/-) mice did not show either activation of CD8(+) T cells or a decrease in the number of cysts in the brain. Transfer of splenic adherent cells from WT into STAT6(-/-) mice induced activation of CD8(+) T cells and decreased the number of cysts in the brain. Expression of CD86 on splenic dendritic cells and IL-12 p40 production were weaker in STAT6(-/-) than in WT mice after T. gondii infection. These results indicate that STAT6 signalling is important in CD8(+) T-cell activation, possibly through regulation of antigen-presenting cells, which could suppress T. gondii infection in the brain.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Toxoplasmose Cerebral
/
Linfócitos T CD8-Positivos
/
Fator de Transcrição STAT6
Limite:
Animals
Idioma:
En
Ano de publicação:
2009
Tipo de documento:
Article