Extinguishing maternal immune responses during pregnancy: implications for immunosuppression.
Mammals owe their existence to immunosuppressive processes that prevent fetal rejection in utero. Blocking tryptophan catabolism during murine pregnancy allows maternal T cells to provoke fetal allograft rejection. Cells expressing indoleamine 2,3-dioxygenase (IDO), which catabolizes tryptophan, prevent T cell cycle progression and enhance activation induced T cell death. Here, we discuss the role of cells expressing IDO in regulating maternal T cell immunity during pregnancy and consider whether this mechanism might contribute to immunological discrimination by promoting T cell tolerance in other circumstances.
Mellor
A L
AL
Medical College of Georgia, Program in Molecular Immunology, Institute of Molecular Medicine and Genetics, Medical College of Georgia, 1120 15th Street, Augusta, GA 30912, USA. amellor@mail.mcg.edu
Munn
D H
DH
D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D016923:Cell Death; D005260:Female; D006801:Humans; D007108:Immune Tolerance; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase; D008213:Lymphocyte Activation; D008431:Maternal-Fetal Exchange / Q000276:immunology; D051379:Mice; D011247:Pregnancy / Q000276:immunology* / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D014364:Tryptophan / Q000276:immunology / Q000378:metabolism; D014366:Tryptophan Oxygenase / Q000378:metabolism
D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase; D014364:Tryptophan; D014366:Tryptophan Oxygenase