Toll-like receptor 9-mediated induction of the immunosuppressive pathway of tryptophan catabolism.
A series of recent studies, including an article in this issue of the European Journal of Immunology, have demonstrated that the administration of CpG-rich oligodeoxynucleotides (CpG-ODN) in experimental settings may lead to the activation of the immunosuppressive pathway of tryptophan catabolism, depending on several factors, including the route of CpG-ODN administration. These studies call attention to the need for a careful evaluation of the modalities of inclusion of CpG-ODN in vaccines for human use. At the same time, these studies may offer novel opportunities for use of CpG-ODN as immunosuppressive agents and may also lead to an improved understanding of the cellular events mediated by Toll-like receptor 9 signaling.
Fallarino
Francesca
F
Department of Experimental Medicine, University of Perugia, Perugia, Italy. fllfnc@tin.it
Puccetti
Paolo
P
D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000818:Animals; D006801:Humans; D007165:Immunosuppression Therapy; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase / Q000378:metabolism; D009838:Oligodeoxyribonucleotides / Q000008:administration & dosage / Q000276:immunology*; D051217:Toll-Like Receptor 9 / Q000276:immunology*; D014364:Tryptophan / Q000378:metabolism*
D000276:Adjuvants, Immunologic; C408982:CPG-oligonucleotide; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase; D009838:Oligodeoxyribonucleotides; D051217:Toll-Like Receptor 9; D014364:Tryptophan