title: In vitro differentiation of human cord blood-derived unrestricted somatic stem cells towards an endodermal pathway.
abstract: BACKGROUND
  Pluripotent unrestricted somatic stem cells (USSC) from UC blood can differentiate into hepatic cells in the in utero sheep model, resulting in 20% human albumin-producing parenchymal hepatic cells without cell fusion or tumor-formation events. Additionally, we have shown in vitro differentiation of USSC by hepatocyte growth factor and oncostatin M induction, causing changes in the gene expression towards the endodermal lineage. Positive glycogen synthase expression and a positive periodic acid-schiff reaction demonstrated a functional production of polysaccharides in the cells.
  
  
  METHODS
  We describe the in vitro differentiation of USSC towards an endodermal pathway using different matrices, growth factors and organic substances. Also, co-cultures of USSC with primary cells of endodermal tissue were prepared to mimic the biologic niche. We investigated the effect of direct co-culture of USSC with primary rat hepatocytes or with sheep tissue of endodermal origin. Direct co-cultures were set up to ensure cell-cell contacts. For co-cultures without cell-cell contacts, transwell inlays with 1-microm membranes were used to separate the cells. Furthermore, the effect of endodermally conditioned medium was investigated. Changes in the gene expression patterns were analyzed by RT-PCR.
  
  
  RESULTS
  We have shown that USSC can differentiate in vitro into an endodermal-like cell with a phenotype similar to hepatic cells. Differentiation of USSC with growth factors, retinoic acid, matrigel matrix and different co-cultures led to an increased expression of albumin and also to the detection of GSC, SOX 17, Cyp2B6, Cyp3A4, Gys2, HNF4a, ISL-1 and Nkx6.1. In addition, functional albumin secretion was observed.
  
  
  CONCLUSIONS
  Although the differentiation assays demonstrated here produce only an immature hepatocyte-like cell, endodermaly differentiated USSC might be a useful alternative for cell replacement in the future.
authors.affiliation: Institute for Transplantation Diagnostics and Cell Therapeutics, University of Duesseldorf Medical School, Duesseldorf, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Sensken
authors.forename: S
authors.initials: S
authors.lastname: Waclawczyk
authors.forename: A S
authors.initials: AS
authors.lastname: Knaupp
authors.forename: T
authors.initials: T
authors.lastname: Trapp
authors.forename: J
authors.initials: J
authors.lastname: Enczmann
authors.forename: P
authors.initials: P
authors.lastname: Wernet
authors.forename: G
authors.initials: G
authors.lastname: Kogler
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D018920:Coculture Techniques; D003094:Collagen / Q000187:drug effects; D017077:Culture Media, Conditioned; D004338:Drug Combinations; D004707:Endoderm / Q000166:cytology* / Q000187:drug effects; D005312:Fetal Blood / Q000166:cytology* / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects; D017228:Hepatocyte Growth Factor / Q000494:pharmacology; D022781:Hepatocytes / Q000166:cytology / Q000187:drug effects; D006801:Humans; D007797:Laminin / Q000187:drug effects; D053683:Oncostatin M / Q000494:pharmacology; D010503:Periodic Acid-Schiff Reaction; D011509:Proteoglycans / Q000187:drug effects; D051381:Rats; D012709:Serum Albumin / Q000378:metabolism; D012756:Sheep; D013234:Stem Cells / Q000166:cytology* / Q000187:drug effects; D014212:Tretinoin / Q000494:pharmacology
chemical_list: D017077:Culture Media, Conditioned; D004338:Drug Combinations; D007797:Laminin; D011509:Proteoglycans; D012709:Serum Albumin; D053683:Oncostatin M; C059485:matrigel; D014212:Tretinoin; D017228:Hepatocyte Growth Factor; D003094:Collagen