title: Induction of hepatic differentiation in embryonic stem cells by co-culture with embryonic cardiac mesoderm.
abstract: BACKGROUND
  Modifications in vitro have been used to direct embryonic stem (ES) cells toward endodermal phenotypes including hepatocytes; however, developmental correlates and evidence of biologic activity is lacking, and critical cell-cell interactions have not been investigated. In this study, we hypothesized that cardiac mesoderm (CM) signals ES cells in co-culture to undergo differentiation toward early hepatocyte lineage as determined by morphology and induction of genes essential for endodermal competence and hepatocyte development.
  
  
  METHODS
  Green fluorescent protein ES derived from A129 mice were cultured with or without embryonic chick cardiac mesoderm. Cultures from day 1, 2, and 4 were analyzed for colony formation and ES morphology and 10(6) ES-derived cells were isolated for mRNA analysis.
  
  
  RESULTS
  ES in co-culture with CM displayed colony formation, polymorphic appearance, and definitive interface with CM. In addition, ES + CM co-culture activated crucial transcription factors (sox 17alpha, HNF3beta, and GATA 4) required for hepatocyte development by day 1. mRNA for albumin and especially a-fetoprotein were also increased by culture days 2 and 4.
  
  
  CONCLUSIONS
  ES cells co-cultured with CM display morphology and gene expression pattern required for hepatocyte differentiation and appear to recapitulate the molecular events of hepatogenesis.
authors.affiliation: Department of Surgery, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Fair
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Cairns
authors.forename: Michael
authors.initials: M
authors.lastname: Lapaglia
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.forename: Anthony A
authors.initials: AA
authors.lastname: Meyer
authors.forename: Hyung
authors.initials: H
authors.lastname: Kim
authors.forename: Seigo
authors.initials: S
authors.lastname: Hatada
authors.forename: Oliver
authors.initials: O
authors.lastname: Smithies
authors.forename: Larysa
authors.initials: L
authors.lastname: Pevny
mesh_terms: D000418:Albumins / Q000235:genetics; D000818:Animals; D002454:Cell Differentiation; D002478:Cells, Cultured; D002642:Chick Embryo; D018920:Coculture Techniques; D004268:DNA-Binding Proteins / Q000378:metabolism; D004622:Embryo, Mammalian / Q000166:cytology; D050991:GATA4 Transcription Factor; D049452:Green Fluorescent Proteins; D006321:Heart / Q000196:embryology*; D051542:Hepatocyte Nuclear Factor 3-beta; D007202:Indicators and Reagents; D008099:Liver / Q000166:cytology / Q000196:embryology*; D008164:Luminescent Proteins; D008648:Mesoderm / Q000502:physiology*; D051379:Mice; D008815:Mice, Inbred Strains; D009687:Nuclear Proteins / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism; D013997:Time Factors; D014157:Transcription Factors / Q000378:metabolism; D000509:alpha-Fetoproteins / Q000235:genetics
chemical_list: D000418:Albumins; D004268:DNA-Binding Proteins; C496503:Foxa2 protein, mouse; D050991:GATA4 Transcription Factor; D007202:Indicators and Reagents; D008164:Luminescent Proteins; D009687:Nuclear Proteins; D011506:Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; D000509:alpha-Fetoproteins; D051542:Hepatocyte Nuclear Factor 3-beta; D049452:Green Fluorescent Proteins