title: Luteinizing hormone contributes to fetal tolerance by regulating adaptive immune responses.
abstract: OBJECTIVE
  Pregnancy hormones were proposed to be crucially involved in fetal tolerance. Recently, we showed that human chorionic gonadotropin (hCG) not only increases the number and activity of regulatory T cells (Treg) but also retains tolerogenic dendritic cells (DCs). Here, we investigate whether the highly homologous luteinizing hormone (LH) modulates Treg number and DC phenotype and thereby supports pregnancy.
  
  
  METHODS
  Abortion-prone females were treated with LH or PBS on different gestation days. Pregnancy outcome and the number and phenotype of Treg and DCs were evaluated in the periphery and locally.
  
  
  RESULTS
  We discovered that LH application completely prevented fetal rejection in abortion-prone females. This protective effect was associated with a Treg augmentation peripherally and locally. Moreover, LH reduced the number of total and mature DCs.
  
  
  CONCLUSIONS
  Our data suggest that LH, similar to hCG, is involved in the regulation of adaptive immune responses, thus contributing to 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.forename: Eileen
authors.initials: E
authors.lastname: Poloski
authors.forename: Dominique
authors.initials: D
authors.lastname: Spörke
authors.forename: Ana C
authors.initials: AC
authors.lastname: Zenclussen
mesh_terms: D000022:Abortion, Spontaneous / Q000276:immunology / Q000473:pathology / Q000517:prevention & control*; D056704:Adaptive Immunity / Q000187:drug effects*; D000818:Animals; D003433:Crosses, Genetic; D003713:Dendritic Cells / Q000166:cytology / Q000187:drug effects* / Q000276:immunology; D005260:Female; D005333:Fetus; D005865:Gestational Age; D006801:Humans; D007108:Immune Tolerance / Q000187:drug effects*; D007986:Luteinizing Hormone / Q000494:pharmacology*; D018655:Lymphocyte Count; D051379:Mice; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D011247:Pregnancy; D050378:T-Lymphocytes, Regulatory / Q000166:cytology / Q000187:drug effects* / Q000276:immunology
chemical_list: D007986:Luteinizing Hormone
keywords: Dendritic cell; Treg; luteinizing hormone; pregnancy