title: Native umbilical cord matrix stem cells express hepatic markers and differentiate into hepatocyte-like cells.
abstract: OBJECTIVE
  Umbilical cord matrix stem cells (UCMSCs) are able to differentiate into mesodermal and ectodermal lineages. The present study investigates the differentiation potential of human UCMSCs into hepatic lineage.
  
  
  METHODS
  We isolated human UCMSCs and characterized them in vitro by measuring their expansion potential, by assessing expression of mesenchymal stem cell (MSC) markers, and by evaluating their ability to differentiate into adipocytes and osteocytes. UCMSCs were thereafter subjected to a hepatogenic differentiation protocol. Expression of hepatic and MSC markers in differentiated cells was analyzed by reverse-transcription polymerase chain reaction, flow cytometry, and immunocytochemical assays and compared with undifferentiated UCMSCs and freshly isolated liver cells. UCMSCs were transplanted into livers of hepatectomized-SCID mice, and engraftment capacity was investigated by detection of human nucleus and mitochondria and human hepatic-specific proteins.
  
  
  RESULTS
  In vitro expanded UCMSCs constitutively expressed markers of hepatic lineage, including albumin, alpha-fetoprotein, cytokeratin-19, connexin-32, and dipeptidyl peptidase IV. In vitro-differentiated UCMSCs exhibited hepatocyte-like morphology, up-regulated several hepatic markers, stored glycogen, produced urea, and exhibited an inducible CYP 3A4 activity. However, absence of some hepatic markers in differentiated UCMSCs, as HepPar1 or hepatocyte nuclear factor 4 (HNF-4), implied that their differentiation did not reach the level of mature hepatocytes. We also noticed that differentiated UCMSCs partially preserved MSC markers. Engraftment capacity of UCMSCs was observed, and expression of human albumin and alpha-fetoprotein was detected 2, 4, and 6 weeks after transplantation in mice livers, while cytokeratin 19 was completely down-regulated.
  
  
  CONCLUSIONS
  We conclude that UCMSCs, with a newly demonstrated endodermic differentiation potential, might be an alternative source for liver-directed cell therapies.
authors.affiliation: HPED Department, PEDI Unit, Laboratory of Pediatric Hepatology and Cell Therapy, Université Catholique de Louvain, Brussels, Belgium.
authors.forename: David
authors.initials: D
authors.lastname: Campard
authors.forename: Philippe A
authors.initials: PA
authors.lastname: Lysy
authors.forename: Mustapha
authors.initials: M
authors.lastname: Najimi
authors.forename: Etienne Marc
authors.initials: EM
authors.lastname: Sokal
mesh_terms: D017667:Adipocytes / Q000378:metabolism; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002454:Cell Differentiation; D019070:Cell Lineage; D049109:Cell Proliferation; D048430:Cell Shape; D002478:Cells, Cultured; D005260:Female; D053686:Fetal Stem Cells / Q000378:metabolism / Q000637:transplantation; D006498:Hepatectomy; D022781:Hepatocytes / Q000378:metabolism; D006801:Humans; D008099:Liver / Q000166:cytology* / Q000378:metabolism / Q000601:surgery; D008115:Liver Regeneration; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000378:metabolism; D051379:Mice; D016513:Mice, SCID; D010011:Osteocytes / Q000378:metabolism; D010641:Phenotype; D013997:Time Factors; D014470:Umbilical Cord / Q000166:cytology* / Q000378:metabolism
chemical_list: D015415:Biomarkers