title: Role of PD1/PDL1 pathway, and TH17 and treg cells in maternal tolerance to the fetus.
abstract: Tolerance of the fetus by the maternal immune system is regulated through various mechanisms involving the different immune cells, both in the periphery and locally at the feto-maternal interface. The maternal T lymphocytes are aware of the paternal fetal antigens and a state of dynamic T cell homeostasis is maintained in the uterus during gestation, which involves increase in antigen-specific regulatory T cell (Treg) proliferation, increase in apoptosis of antigen-specific effector T cells, and inhibition of excessive inflammation post successful implantation to ensure tolerance to the fetus. The Tregs play an important role in the maintenance of tolerance during gestation. Recently, the inflammatory T helper type 17 (Th17) cells are reported to have a role in loss of tolerance to the fetus. The interaction between costimulatory molecule programmed death 1 (PD1) and its ligand PDL1 is known to play a role in regulating both the Tregs and Th17 cells. Here we discuss how the PD1/PDL1 pathway affects these two T cell populations and its role in feto-maternal tolerance.
authors.forename: Sudipta
authors.initials: S
authors.lastname: Tripathi
authors.affiliation: Transplantation Research Center, Boston Children's Hospital and Brigham and Women's Hospital; Renal Division, Harvard Medical School, Boston, USA.
authors.forename: Indira
authors.initials: I
authors.lastname: Guleria
mesh_terms: D000818:Animals; D060890:B7-H1 Antigen / Q000276:immunology*; D005333:Fetus / Q000276:immunology*; D006801:Humans; D007108:Immune Tolerance / Q000276:immunology*; D061026:Programmed Cell Death 1 Receptor / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000166:cytology* / Q000276:immunology; D058504:Th17 Cells / Q000166:cytology* / Q000276:immunology
chemical_list: D060890:B7-H1 Antigen; C423236:CD274 protein, human; C105992:PDCD1 protein, human; D061026:Programmed Cell Death 1 Receptor