title: Mineralised Collagen Scaffolds Loaded with Stromal Cell-derived Factor-1 Improve Mandibular Bone Regeneration.
abstract: OBJECTIVE
  To create an in situ matrix environment conducive to stem cells from host bone marrow to promote bone regeneration.
  
  
  METHODS
  Three-dimensional porous, mineralised collagen (MC) scaffolds were prepared using a freeze-drying process. The microstructure of scaffolds was observed by field emission scanning electron microscopy. The Bose BioDynamic test system was applied to examine their mechanical properties in wet conditions. The effect of scaffolds loaded with stromal cellderived factor-1α (SDF-1α) on migration of stem cells was assessed using a 24-well transwell system. SDF-1α-loaded scaffolds were implanted in the critical size defect in rats and histological staining was used to evaluate the new bone formation.
  
  
  RESULTS
  Mechanical testing showed that the MC scaffold featured an increased Young's modulus compared with the pure collagen (Col) scaffold in wet conditions. In addition, the MC scaffold loaded with SDF-1α chemokine improved bone marrow stromal cells' migration. When implanted in mandibular bone defects with 5 mm diameter, the MC scaffolds containing SDF-1α significantly improved the formation of new bone and blood capillaries within the scaffolds, compared with the SDF-1α-loaded Col scaffolds and the control group.
  
  
  CONCLUSIONS
  The mineralised collagen scaffolds loaded with SDF-1α, which creates a matrix environment conducive to stem cell migration, can be exploited to improve bone self-repair as an alternative to contemporary cell seeding approaches.
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.forename: Shuai
authors.initials: S
authors.lastname: Liu
authors.forename: Yu
authors.initials: Y
authors.lastname: Fu
authors.forename: Da Tong
authors.initials: DT
authors.lastname: Chang
authors.forename: Yan Heng
authors.initials: YH
authors.lastname: Zhou
mesh_terms: D000818:Animals; D001861:Bone Regeneration / Q000502:physiology*; D002465:Cell Movement / Q000187:drug effects; D002469:Cell Separation; D054377:Chemokine CXCL12 / Q000627:therapeutic use*; D002633:Chemotaxis / Q000187:drug effects; D003094:Collagen / Q000737:chemistry*; D015194:Diffusion Chambers, Culture; D055119:Elastic Modulus; D008297:Male; D008334:Mandible / Q000098:blood supply / Q000187:drug effects; D008336:Mandibular Diseases / Q000628:therapy*; D059630:Mesenchymal Stem Cells / Q000187:drug effects; D008855:Microscopy, Electron, Scanning; D018919:Neovascularization, Physiologic / Q000187:drug effects; D010012:Osteogenesis / Q000187:drug effects; D011897:Random Allocation; D017207:Rats, Sprague-Dawley; D013314:Stress, Mechanical; D013499:Surface Properties; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: C575935:CXCL12 protein, rat; D054377:Chemokine CXCL12; D003094:Collagen