title: Progesterone-driven local regulatory T cell induction does not prevent fetal loss in the CBA/J×DBA/2J abortion-prone model.
abstract: OBJECTIVE
  Best known for its endocrine and immunologic properties, progesterone (P4) is a pivotal player for pregnancy success. However, the immunologic actions underlying P4 protection are not completely understood. Here, we investigated whether P4 application in a murine abortion-prone combination regulates regulatory T cells (Treg) and dendritic cells (DCs) and thereby affects pregnancy outcome.
  
  
  METHODS
  Progesterone or vehicle was applied to DBA/2J-mated CBA/J abortion-prone animals in early pregnancy. On gestation day 10, peripheral and local DC and Treg numbers were analyzed and pregnancy outcome was determined.
  
  
  RESULTS
  Progesterone application provoked a significant increase in the uterine Treg pool but did not alter the abortion rate. Moreover, no significant changes could be observed in peripheral Treg levels and DC numbers after P4 application.
  
  
  CONCLUSIONS
  Our findings suggest that P4-induced local Treg elevation is not sufficient to overcome fetal rejection in this specific model of disturbed fetal tolerance.
authors.affiliation: Department of Experimental Obstetrics and Gynecology, Medical Faculty, Otto-von-Guericke University, Magdeburg, Germany.
authors.forename: Anne
authors.initials: A
authors.lastname: Schumacher
authors.affiliation: Department of Experimental Obstetrics and Gynecology, Medical Faculty, Otto-von-Guericke University, Magdeburg, Germany.
authors.forename: Dominique
authors.initials: D
authors.lastname: Dauven
authors.affiliation: Department of Experimental Obstetrics and Gynecology, Medical Faculty, Otto-von-Guericke University, Magdeburg, Germany.
authors.forename: Ana C
authors.initials: AC
authors.lastname: Zenclussen
mesh_terms: D000028:Abortion, Induced; D000022:Abortion, Spontaneous / Q000276:immunology*; D000818:Animals; D003713:Dendritic Cells / Q000276:immunology*; D005260:Female; D006801:Humans; D007108:Immune Tolerance; D051379:Mice; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D011247:Pregnancy; D011256:Pregnancy Outcome; D011374:Progesterone / Q000378:metabolism*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D014599:Uterus / Q000473:pathology*
chemical_list: D011374:Progesterone
keywords: P4; dendritic cells; fetal tolerance; regulatory T cells