title: The role of systemically delivered bone marrow-derived mesenchymal stem cells in the regeneration of periodontal tissues.
abstract: OBJECTIVE
  Recent studies have shown that periodontal ligament stem cells (PDLSCs) play a key role in periodontal regeneration. However, the origin of these cells remains unclear. Meanwhile, bone marrow is thought to be the most common source of adult stem cells in many tissues and organs. Thus, the present investigation sought to determine whether systemically delivered bone marrow-derived mesenchymal stem cells (BM-MSCs) could participate in periodontal regeneration and differentiate into periodontal-specific cells and to explore the origin of PDLSCs.
  
  
  METHODS
  Enhanced green fluorescent protein (EGFP)-labeled BMMSCs were delivered into lethally irradiated rats by intra-bone marrow (IBM) transplantation. Four weeks after transplantation, periodontal defects with and without infection of anaerobic cultured Porphyromonas gingivalis were established. The animals were killed 1, 2, 4, or 6 weeks after periodontal defect surgery. Histomorphologic analysis, direct observation with the fluorescence microscope, and immunohistochemical staining were performed to evaluate the localization and differentiation of BM-MSCs.
  
  
  RESULTS
  EGFP-positive BM-MSCs could be observed as early as 1 week after surgery, and the number of EGFP-positive cells reached a maximum at 2 weeks. Meanwhile, EGFP-positive cells were observed in the newly formed bone, PDL, and cementum 4 weeks after surgery. Immunohistochemical staining verified that EGFP-positive BM-MSCs could differentiate into osteoblasts.
  
  
  CONCLUSIONS
  These findings provide direct evidence that BM-MSCs can participate in and modulate periodontal regeneration.
authors.forename: Meijiao
authors.initials: M
authors.lastname: Yu
authors.forename: Shaohua
authors.initials: S
authors.lastname: Ge
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.forename: Yong
authors.initials: Y
authors.lastname: Wen
authors.forename: Xinlong
authors.initials: X
authors.lastname: Yan
authors.forename: Quan
authors.initials: Q
authors.lastname: Zeng
authors.forename: Wen
authors.initials: W
authors.lastname: Yue
authors.forename: Pishan
authors.initials: P
authors.lastname: Yang
authors.forename: Xuetao
authors.initials: X
authors.lastname: Pei
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000502:physiology*; D016026:Bone Marrow Transplantation; D002454:Cell Differentiation / Q000502:physiology*; D003739:Dental Cementum / Q000166:cytology; D005260:Female; D049452:Green Fluorescent Proteins; D045164:Mesenchymal Stem Cell Transplantation / Q000379:methods*; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D010006:Osteoblasts; D010513:Periodontal Ligament / Q000166:cytology / Q000502:physiology; D010519:Periodontium / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012038:Regeneration / Q000502:physiology*
chemical_list: C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins