Indoleamine 2,3-dioxygenase in hematopoietic stem cell transplantation.
Hematopoietic stem cell transplantation (HSCT) is complicated by unwelcome side-effects that arise on the basis of an altered immune system. Infectious complications and alloreactive T-cell responses trigger a process of ongoing immune activation and inflammation. Negative-feedback mechanisms to counteract inflammation involve the induction of the immunoregulatory enzyme indoleamine 2,3-dioxygenase (IDO), which mediates anti-inflammatory activities and T-cell inhibition via tryptophan catabolism. However, persistent immune activation and generalized release of pro-inflammatory cytokines deviate immune regulation towards chronic suppression incapable to abrogate the inflammatory response. This review focuses on the unique role of tryptophan catabolism in modulating inflammatory processes and T-cell responses after HSCT.
Hainz
U
U
Children's Cancer Research Institute, St. Anna Children's Hospital, Transplantation Immunology, Kinderspitalgasse 6, A-1090 Vienna, Austria.
Jürgens
B
B
Wekerle
T
T
Seidel
M G
MG
Heitger
Andreas
A
D000818:Animals; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology
D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase