title: Direct contact with mesenchymal stromal cells affects migratory behavior and gene expression profile of CD133+ hematopoietic stem cells during ex vivo expansion.
abstract: OBJECTIVE
  To investigate the impact of direct contact between mesenchymal stromal cells (MSCs) and CD133(+) hematopoietic stem cells in terms of expansion potential, differentiation, migratory capacity, and gene expression profile.
  
  
  METHODS
  CD133(+)-purified hematopoietic progenitor cells were cultured for 7 days on subconfluent MSCs supplemented with growth-factor-containing medium. After ex vivo expansion, nonadherent and adherent cells were collected and analyzed separately.
  
  
  RESULTS
  The adherent cell population was less differentiated than the nonadherent fraction. CXCR4 was upregulated in the adherent fraction, which was associated with a higher migration capacity toward a stromal cell-derived factor-1 gradient. Colony-forming unit granulocyte-macrophage and long-term culture-initiation cell assays demonstrated a higher clonogenicity and repopulating capacity of the adherent fraction. Genes involved in adhesion, cell-cycle control, motility, and self-renewal were more highly expressed in the adherent fraction.
  
  
  CONCLUSIONS
  Adhesion and direct cell-to-cell contact with an MSC feeder layer supports ex vivo expansion, migratory potential, and stemness of CD133(+) hematopoietic progenitor cells.
authors.affiliation: Medizinische Klinik und Poliklinik I, University Hospital Carl-Gustav-Carus, Dresden, Germany. nael.alakel@uniklinikum-dresden.de
authors.forename: Nael
authors.initials: N
authors.lastname: Alakel
authors.forename: Duohui
authors.initials: D
authors.lastname: Jing
authors.forename: Katrin
authors.initials: K
authors.lastname: Muller
authors.forename: Martin
authors.initials: M
authors.lastname: Bornhauser
authors.forename: Gerhard
authors.initials: G
authors.lastname: Ehninger
authors.forename: Rainer
authors.initials: R
authors.lastname: Ordemann
mesh_terms: D000071916:AC133 Antigen; D015703:Antigens, CD / Q000378:metabolism*; D015153:Blotting, Western; D002448:Cell Adhesion; D002455:Cell Division / Q000502:physiology; D002465:Cell Movement / Q000502:physiology*; D005434:Flow Cytometry; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006023:Glycoproteins / Q000378:metabolism*; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism*; D010455:Peptides / Q000378:metabolism*; D017154:Stromal Cells / Q000166:cytology / Q000378:metabolism*; D013499:Surface Properties
chemical_list: D000071916:AC133 Antigen; D015703:Antigens, CD; D006023:Glycoproteins; C000606023:PROM1 protein, human; D010455:Peptides