title: [Effects of mechanical strain on human osteoblastic precursor cells in type I collagen matrices].
abstract: BACKGROUND
  The aim of the present study was to investigate the effect of mechanical strain on human osteoblastic precursor cells in a three-dimensional scaffold.
  
  
  METHODS
  Osteoblastic precursor cells were seeded in a collagen type I gel and mechanically stretched by daily application of cyclic uniaxial strain. The expression of histone H4, core binding factor 1, alkaline phosphatase, osteopontin, osteocalcin, and collagen type I was investigated by analysing the mRNA. Cell and matrix orientation were investigated by scanning electron microscopy.
  
  
  RESULTS
  Cyclic stretching increased cell proliferation. The expression of osteogenic markers was slightly increased by mechanical strain. The cells and matrix were strictly oriented in the stress direction.
  
  
  CONCLUSIONS
  The application of mechanical load might have a beneficial effect on the quality and quantity of generated bone tissue and might be a important factor in tissue engineering of bone.
authors.affiliation: Kompetenznetz Biomaterialien Baden-Württemberg, Institut für Unfallchirurgische Forschung und Biomechanik der Universität Ulm. anita.ignatius@medizin.uni-ulm.de
authors.forename: A
authors.initials: A
authors.lastname: Ignatius
authors.forename: H
authors.initials: H
authors.lastname: Blessing
authors.forename: A
authors.initials: A
authors.lastname: Liedert
authors.forename: D
authors.initials: D
authors.lastname: Kaspar
authors.forename: L
authors.initials: L
authors.lastname: Kreja
authors.forename: B
authors.initials: B
authors.lastname: Friemert
authors.forename: L
authors.initials: L
authors.lastname: Claes
mesh_terms: D000469:Alkaline Phosphatase / Q000235:genetics; D001861:Bone Regeneration / Q000502:physiology*; D002454:Cell Differentiation / Q000502:physiology*; D002455:Cell Division / Q000502:physiology*; D002460:Cell Line; D024042:Collagen Type I / Q000235:genetics; D050660:Core Binding Factors; D015870:Gene Expression / Q000502:physiology; D006657:Histones / Q000235:genetics; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D008855:Microscopy, Electron, Scanning; D009363:Neoplasm Proteins / Q000235:genetics; D010006:Osteoblasts / Q000166:cytology*; D053495:Osteopontin; D010812:Physical Stimulation / Q000295:instrumentation*; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics; D012795:Sialoglycoproteins / Q000235:genetics; D033581:Stem Cell Transplantation; D023822:Tissue Engineering / Q000379:methods*; D014157:Transcription Factors / Q000235:genetics
chemical_list: D024042:Collagen Type I; D050660:Core Binding Factors; D006657:Histones; D009363:Neoplasm Proteins; D012333:RNA, Messenger; C506895:SPP1 protein, human; D012795:Sialoglycoproteins; D014157:Transcription Factors; D053495:Osteopontin; D000469:Alkaline Phosphatase