Tryptophan catabolism in IDO+ plasmacytoid dendritic cells.
Plasmacytoid dendritic cells (pDCs) represent a specialized cell population that produces large amounts of type I interferons, the so-called natural interferon-producing cells. Recently, murine and human pDCs have been credited with a unique ability to express indoleamine 2,3-dioxygenase (IDO) and to mediate immunosuppression in specific settings. This suggests an important role for IDO-expressing pDCs in controlling the balance of inflammation and tolerance. Here we review recent advances in our understanding of how these cells may be critical at the interface of inflammation and tolerance and discuss the potential for therapeutic IDO modulation as an immunoregulatory maneuver targeting pDC function.
Fallarino
Francesca
F
Department of Experimental Medicine, Section of Pharmacology, University of Perugia, Via del Giochetto, Perugia 06126, Italy. fllfnc@tin.it
Gizzi
S
S
Mosci
P
P
Grohmann
U
U
Puccetti
P
P
D000818:Animals; D017209:Apoptosis; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007108:Immune Tolerance; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase / Q000276:immunology* / Q000378:metabolism; D007737:Kynurenine / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology; D014364:Tryptophan / Q000276:immunology / Q000378:metabolism
D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase; D007737:Kynurenine; D014364:Tryptophan