Cutting edge: silencing suppressor of cytokine signaling 3 expression in dendritic cells turns CD28-Ig from immune adjuvant to suppressant - PubMed (original) (raw)

Comparative Study

. 2005 Jun 1;174(11):6582-6.

doi: 10.4049/jimmunol.174.11.6582.

Affiliations

Comparative Study

Cutting edge: silencing suppressor of cytokine signaling 3 expression in dendritic cells turns CD28-Ig from immune adjuvant to suppressant

Ciriana Orabona et al. J Immunol. 2005.

Abstract

CTLA-4-Ig and CD28-Ig are both agonist ligands of B7 coreceptor molecules on mouse dendritic cells (DCs), yet they bias the downstream response in opposite directions, and CTLA-4-Ig promotes tolerance, whereas CD28-Ig favors the onset of immunity. Although B7 engagement by either ligand leads to a mixed cytokine response, a dominant IL-6 production in response to CD28-Ig prevents the IFN-gamma-driven induction of immunosuppressive tryptophan catabolism mediated by IDO. In the present study, we show that silencing the expression of suppressor of cytokine signaling 3 (SOCS3) in DCs by RNA interference renders CD28-Ig capable of activating IDO, likely as a result of unrestrained IFN-gamma signaling and IFN-gamma-like actions of IL-6. Thus, in the absence of SOCS3, CD28-Ig becomes immunosuppressive and mimics the action of CTLA-4-Ig on tryptophan catabolism.

PubMed Disclaimer

Similar articles

Cited by

Publication types

MeSH terms

Substances

LinkOut - more resources