title: Toll-like receptor 4 expression in decidual cells and interstitial trophoblasts across human pregnancy.
abstract: OBJECTIVE
  Toll-like receptor-4 (TLR-4) protects against Gram-negative bacteria expressed lipopolysaccharide and 'danger signals' from injured or dying cells. Although decidual cells (DCs) and interstitial trophoblasts (ITs) are in close contact, TLR-4 has been studied extensively only in ITs.
  
  
  METHODS
  Formalin-fixed, paraffin-embedded serial sections of endometrium in follicular and luteal phases and deciduas from first and second trimester elective terminations and third trimester normal deliveries were immunostained for TLR-4, trophoblast-specific cytokeratin, and DC-specific vimentin. HSCORE assessed TLR-4 immunostaining in DCs versus ITs.
  
  
  RESULTS
  TLR-4 HSCORES were significantly higher in: (i) first trimester DCs than luteal phase pre-decidual stromal cells; (ii) first and third versus second trimester DCs, but similar between third trimester deciduas parietalis and basalis; (iii) first versus second trimester ITs; (iv) DCs versus ITs across gestation.
  
  
  CONCLUSIONS
  Higher TLR-4 in DCs than ITs suggests DCs as primary targets for Gram-negative bacteria and/or inflammation-related danger signals.
authors.affiliation: Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, CT, USA. Frederick.Schatz@osumc.edu
authors.forename: Frederic
authors.initials: F
authors.lastname: Schatz
authors.forename: Umit A
authors.initials: UA
authors.lastname: Kayisli
authors.forename: Emre
authors.initials: E
authors.lastname: Vatandaslar
authors.forename: Nehir
authors.initials: N
authors.lastname: Ocak
authors.forename: Seth
authors.initials: S
authors.lastname: Guller
authors.forename: Vikki M
authors.initials: VM
authors.lastname: Abrahams
authors.forename: Graciela
authors.initials: G
authors.lastname: Krikun
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Lockwood
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D003656:Decidua / Q000276:immunology* / Q000473:pathology; D005260:Female; D005498:Follicular Phase / Q000276:immunology; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D007150:Immunohistochemistry; D053552:Keratin-7 / Q000235:genetics / Q000378:metabolism; D008183:Luteal Phase / Q000276:immunology; D011247:Pregnancy; D047928:Premature Birth / Q000276:immunology*; D051197:Toll-Like Receptor 4 / Q000235:genetics / Q000378:metabolism*; D014327:Trophoblasts / Q000276:immunology*; D015854:Up-Regulation; D014746:Vimentin / Q000235:genetics / Q000378:metabolism
chemical_list: D015415:Biomarkers; D053552:Keratin-7; D051197:Toll-Like Receptor 4; D014746:Vimentin