title: Immunohistochemical and molecular characterization of the human periosteum.
abstract: OBJECTIVE
  The aim of the present study was to characterize the cell of the human periosteum using immunohistological and molecular methods.
  
  
  METHODS
  Phenotypic properties and the distribution of the cells within the different layers were investigated with immunohistochemical staining techniques and RT-PCR, focussing on markers for stromal stem cells, osteoblasts, osteoclasts and immune cells.
  
  
  RESULTS
  Immunohistochemical results revealed that all stained cells were located in the cambium layer and that most cells were positive for vimentin. The majority of cells consisted of stromal stem cells and osteoblastic precursor cells. The density increased towards the deeper layers of the cambium. In addition, cells positive for markers of the osteoblast, chondrocyte, and osteoclast lineages were found. Interestingly, there were MHC class II-expressing immune cells suggesting the presence of dendritic cells. Using lineage-specific primer pairs RT-PCR confirmed the immunofluorescence microscopy results, supporting that human periosteum serves as a reservoir of stromal stem cells, as well as cells of the osteoblastic, and the chondroblastic lineage, osteoclasts, and dendritic cells.
  
  
  CONCLUSIONS
  Our work elucidates the role of periosteum as a source of cells with a high regenerative capacity. Undifferentiated stromal stem cells as well as osteoblastic precursor cells are dominating in the cambium layer. A new outlook is given towards an immune response coming from the periosteum as MHC II positive immune cells were detected.
authors.affiliation: Department of Trauma, Hand, Plastic and Reconstructive Surgery, University of Würzburg, Würzburg, Germany. frey_s@chirurgie.uni-wuerzburg.de
authors.forename: Sönke Percy
authors.initials: SP
authors.lastname: Frey
authors.forename: Hendrik
authors.initials: H
authors.lastname: Jansen
authors.forename: Stefanie
authors.initials: S
authors.lastname: Doht
authors.forename: Luis
authors.initials: L
authors.lastname: Filgueira
authors.forename: Rene
authors.initials: R
authors.lastname: Zellweger
mesh_terms: D000293:Adolescent; D000328:Adult; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D007155:Immunologic Factors / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D010006:Osteoblasts / Q000166:cytology* / Q000276:immunology*; D010521:Periosteum / Q000166:cytology* / Q000276:immunology*; D017154:Stromal Cells / Q000166:cytology* / Q000276:immunology*; D055815:Young Adult
chemical_list: D007155:Immunologic Factors