title: Cultured human epithelium: human umbilical cord blood stem cells differentiate into keratinocytes under in vitro conditions.
abstract: BACKGROUND
  Stem cells have the capacity to renew or to give rise to a specialized cell types. Human umbilical cord blood (HUCB) has been explored as an alternative source of stem cells. However, its potential to differentiate into cells of other tissues is still under discussion. The aim of our study was to evaluate if HUCB stem cells could differentiate into epithelial cells under in vitro conditions.
  
  
  METHODS
  Human keratinocytes derived from adult female skin donors, were isolated and cultured on fibrin glue/fibroblast gels-control group. In the umbilical cord blood cell group, male umbilical cord blood cells were added at a 1:10 ratio to keratinocytes and co-cultured on the fibrin glue/fibroblasts gel. After 15 days of culture, the sheets were analyzed by use of histochemistry and FISH. DNA was extracted and evaluated by use of polymerase chain reaction (PCR) for detection of Y-chromosome-specific sequences.
  
  
  RESULTS
  In both groups a regular epithelial sheet consisting of three to four layers of cells was formed. Using PCR and FISH, in the umbilical cord blood cell group the presence of Y-chromosome-specific sequences in the cultured keratinocytes could be detected. In the control group, no Y-chromosome-specific sequences could be detected.
  
  
  CONCLUSIONS
  Our findings indicate that umbilical cord blood stem cells differentiate into epithelial cells under in vitro conditions and thereby, might serve as a starting material for isolation and expansion of cells for transplantation in patients with large skin defects.
authors.affiliation: Division of Plastic and Reconstructive Surgery, Vienna Burn Centre, Department of Surgery, Keratinocyte Research Group, General Hospital, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria. lars-peter.kamolz@meduniwien.ac.at
authors.forename: L-P
authors.initials: LP
authors.lastname: Kamolz
authors.forename: A
authors.initials: A
authors.lastname: Kolbus
authors.forename: N
authors.initials: N
authors.lastname: Wick
authors.forename: P R
authors.initials: PR
authors.lastname: Mazal
authors.forename: B
authors.initials: B
authors.lastname: Eisenbock
authors.forename: S
authors.initials: S
authors.lastname: Burjak
authors.forename: G
authors.initials: G
authors.lastname: Meissl
mesh_terms: D000328:Adult; D002454:Cell Differentiation; D002478:Cells, Cultured; D041322:Chromosomes, Human, Y; D005260:Female; D005312:Fetal Blood / Q000166:cytology*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D066298:In Vitro Techniques; D015603:Keratinocytes / Q000166:cytology*; D008297:Male; D016133:Polymerase Chain Reaction; D013234:Stem Cells / Q000166:cytology*