1-Methyl-tryptophan can interfere with TLR signaling in dendritic cells independently of IDO activity.

Independently of IDO Activity TLR Signaling in Dendritic Cells 1-Methyl-Tryptophan Can Interfere with

Indoleamine 2,3-Dioxygenase and Immunological Tolerance during Pregnancy

Indoleamine 2,3-dioxygenase (IDO), an enzyme involved in the catabolism of tryptophan, is expressed by a variety of cells and tissues such as macrophages, dendritic cells, cells of the endocrine system and by the placenta. IFN- γ is the main inducer of this enzyme. IDO acts as an important defense mechanism of innate immunity against pathogens. It also has tumor suppressive activity and prolong...

The indoleamine 2,3-dioxygenase pathway is essential for human plasmacytoid dendritic cell-induced adaptive T regulatory cell generation.

Human plasmacytoid dendritic cells (PDCs) can drive naive, allogeneic CD4(+)CD25(-) T cells to differentiate into CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs). However, the intracellular mechanism or mechanisms underlying PDC-induced Treg generation are unknown. In this study, we show that human PDCs express high levels of IDO, an intracellular enzyme that catabolizes tryptophan degradation...

Inhibition of indoleamine 2,3-dioxygenase in dendritic cells by stereoisomers of 1-methyl-tryptophan correlates with antitumor responses.

Indoleamine 2,3-dioxygenase (IDO) is an immunosuppressive enzyme that contributes to tolerance in a number of biological settings. In cancer, IDO activity may help promote acquired tolerance to tumor antigens. The IDO inhibitor 1-methyl-tryptophan is being developed for clinical trials. However, 1-methyl-tryptophan exists in two stereoisomers with potentially different biological properties, an...

A two-step induction of indoleamine 2,3 dioxygenase (IDO) activity during dendritic-cell maturation.

Prostaglandins, a family of lipidic molecules released during inflammation, display immunomodulatory properties in several models. One use includes exposure of monocyte-derived dendritic cells (DCs) to a cocktail of cytokines that contains prostaglandin E2 (PGE2) for purposes of maturation; such cells are currently being used for cancer immunotherapy trials. Our analysis of the transcription pr...