title: Characterization of a migrative subpopulation of adult human nasoseptal chondrocytes with progenitor cell features and their potential for in vivo cartilage regeneration strategies.
abstract: BACKGROUND
  Progenitor cells display interesting features for tissue repair and reconstruction. In the last years, such cells have been identified in different cartilage types. In this study, we isolated a migrative subpopulation of adult human nasoseptal chondrocytes with progenitor cell features by outgrowth from human nasal septum cartilage. These putative progenitor cells were comparatively characterized with mesenchymal stem cells (MSC) and human nasal septum chondrocytes with respect to their cellular characteristics as well as surface marker profile using flow cytometric analyses. Differentiation capacity was evaluated on protein and gene expression levels.
  
  
  RESULTS
  The migrative subpopulation differentiated into osteogenic and chondrogenic lineages with distinct differences to chondrocytes and MSC. Cells of the migrative subpopulation showed an intermediate surface marker profile positioned between MSC and chondrocytes. Significant differences were found for CD9, CD29, CD44, CD90, CD105 and CD106. The cells possessed a high migratory ability in a Boyden chamber assay and responded to chemotactic stimulation. To evaluate their potential use in tissue engineering applications, a decellularized septal cartilage matrix was either seeded with cells from the migrative subpopulation or chondrocytes. Matrix production was demonstrated immunohistochemically and verified on gene expression level. Along with secretion of matrix metalloproteinases, cells of the migrative subpopulation migrated faster into the collagen matrix than chondrocytes, while synthesis of cartilage specific matrix was comparable.
  
  
  CONCLUSIONS
  Cells of the migrative subpopulation, due to their migratory characteristics, are a potential cell source for in vivo regeneration of nasal cartilage. The in vivo mobilization of nasal cartilage progenitor cells is envisioned to be the basis for in situ tissue engineering procedures, aiming at the use of unseeded biomaterials which are able to recruit local progenitor cells for cartilage regeneration.
authors.affiliation: Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Frauensteige 12, 89075 Ulm, Germany.
authors.forename: A F
authors.initials: AF
authors.lastname: Elsaesser
authors.affiliation: Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Frauensteige 12, 89075 Ulm, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Schwarz
authors.affiliation: Department of Orthopedics, Division for Biochemistry of Joint and Connective Tissue Diseases, University of Ulm, Ulm, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Joos
authors.affiliation: Department of Chemical and Biological Engineering, Institute of Bioprocess Engineering, University of Erlangen, Erlangen, Germany.
authors.forename: L
authors.initials: L
authors.lastname: Koerber
authors.affiliation: Department of Orthopedics, Division for Biochemistry of Joint and Connective Tissue Diseases, University of Ulm, Ulm, Germany.
authors.forename: R E
authors.initials: RE
authors.lastname: Brenner
authors.affiliation: Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Frauensteige 12, 89075 Ulm, Germany.
authors.forename: N
authors.initials: N
authors.lastname: Rotter
keywords: Chondrogenic progenitor cells; Decellularized extracellular matrix; Human nasal septum; Mesenchymal stem cells; Migration; Migrative chondrocyte subpopulation; Tissue engineering