title: Validation of human periodontal ligament-derived cells as a reliable source for cytotherapeutic use.
abstract: OBJECTIVE
  Periodontal ligament (PDL) is a reliable cell source for periodontal regeneration. In this study, an optimal protocol for the extraction, expansion, and characterization of human PDL (hPDL) cells was examined for clinical trials.
  
  
  METHODS
  hPDL tissues were obtained from 41 surgically extracted teeth and digested with enzymes. Human adipose-derived stem cells (hADSCs), bone marrow-derived mesenchymal stem cells (hBMMSCs), and gingival fibroblasts (hGFs) were used for comparison. For each sample, the proliferative capacity, colony-forming ability, alkaline phosphatase activity, differentiation ability, the cell surface antigens, gene expression, and regenerative potential were examined.
  
  
  RESULTS
  hPDL cells were more successfully extracted with collagenase/dispase [29/30 (96.7%)] than with trypsin/EDTA [8/11 (72.7%)], and exhibited osteogenic potential both in vitro and in vivo. The proliferation of hPDL cells was rapid at a low cell density. hPDL cells frequently differentiated into cementoblastic/osteoblastic lineage (∼60%). In contrast, their adipogenic and chondrogenic potentials were lower than those of hADSCs and hBMMSCs. Some genes (NCAM1, S100A4, and periostin) were preferentially expressed in hPDL cells compared with those of hBMMSCs and hGFs. Immunohistochemical studies revealed the expressions of S100A4 and periostin in hPDL tissue.
  
  
  CONCLUSIONS
  A protocol for the successful cultivation and validation of hPDL cells is proposed for clinical settings.
authors.affiliation: Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Iwata
authors.forename: Masayuki
authors.initials: M
authors.lastname: Yamato
authors.forename: Zheng
authors.initials: Z
authors.lastname: Zhang
authors.forename: Shigeki
authors.initials: S
authors.lastname: Mukobata
authors.forename: Kaoru
authors.initials: K
authors.lastname: Washio
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Ando
authors.forename: Jan
authors.initials: J
authors.lastname: Feijen
authors.forename: Teruo
authors.initials: T
authors.lastname: Okano
authors.forename: Isao
authors.initials: I
authors.lastname: Ishikawa
mesh_terms: D017667:Adipocytes / Q000502:physiology; D000293:Adolescent; D000328:Adult; D000469:Alkaline Phosphatase / Q000032:analysis; D000818:Animals; D001854:Bone Marrow Cells / Q000502:physiology; D015815:Cell Adhesion Molecules / Q000032:analysis; D002452:Cell Count; D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation; D017690:Cell Transplantation / Q000379:methods*; D002478:Cells, Cultured; D005260:Female; D005347:Fibroblasts / Q000502:physiology; D020869:Gene Expression Profiling; D005881:Gingiva / Q000166:cytology; D006801:Humans; D008297:Male; D059630:Mesenchymal Stem Cells / Q000502:physiology; D008875:Middle Aged; D010513:Periodontal Ligament / Q000166:cytology*; D051381:Rats; D011916:Rats, Inbred F344; D011923:Rats, Nude; D012038:Regeneration / Q000502:physiology; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins / Q000032:analysis; D013234:Stem Cells / Q000502:physiology; D020858:Tissue and Organ Harvesting; D055815:Young Adult
chemical_list: D015815:Cell Adhesion Molecules; C512835:POSTN protein, human; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins; C077591:S100A4 protein, human; D000469:Alkaline Phosphatase