Human CD4+CD25high regulatory T cells modulate myeloid but not plasmacytoid dendritic cells activation.
J Immunol
; 176(9): 5293-8, 2006 May 01.
Article
en En
| MEDLINE
| ID: mdl-16621995
ABSTRACT
Human CD4(+)CD25(+) regulatory T cells (Treg) play an essential role in the prevention of autoimmune diseases. However, the mechanisms of immune suppression and the spectrum of cells they target in vivo remain incompletely defined. In particular, although Treg directly suppress conventional T cells in vitro, they have been shown to inhibit the Ag-presenting functions of macrophage- and monocyte-derived dendritic cells (DC). We have now studied the maturation of human blood-derived myeloid DC and plasmacytoid DC activated with TLR ligands in the presence of Treg. Preactivated Treg suppressed strongly TLR-triggered myeloid DC maturation, as judged by the blocking of costimulatory molecule up-regulation and the inhibition of proinflammatory cytokines secretion that resulted in poor Ag presentation capacity. Although IL-10 played a prominent role in inhibiting cytokines secretion, suppression of phenotypic maturation required cell-cell contact and was independent of TGF-beta and CTLA-4. In contrast, the acquisition of maturation markers and production of cytokines by plasmacytoid DC triggered with TLR ligands were insensitive to regulatory T cells. Therefore, human Treg may enlist myeloid, but not plasmacytoid DC for the initiation and the amplification of tolerance in vivo by restraining their maturation after TLR stimulation.
Buscar en Google
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Células Dendríticas
/
Receptores de Interleucina-2
/
Linfocitos T Reguladores
/
Células Mieloides
Límite:
Humans
Idioma:
En
Revista:
J Immunol
Año:
2006
Tipo del documento:
Article
País de afiliación:
Francia