title: [Isolation, culture and biological characterization of Beagle stem cells from apical papilla].
abstract: OBJECTIVE
  To isolate and characterize the Beagle stem cells from apical papilla.
  
  
  METHODS
  Apical papilla was severed from the end of freshly  extracted Beagle's young permanent upper anterior teeth, and digested by collagenase type I and dispase for cell culture. The isolated cells were  investigated for stem cell properties by analyzing their colony-forming efficiency, growth characteristics and the expression of mesenchymal stem cell  markers; and evaluating their multidifferentiation potentials including osteogenic, adipogenic, and chondrogenic potentials. Additionally, the cells were  transplanted subcutaneously into immunocompromised mice to observe the mineral tissue formation.
  
  
  RESULTS
  Our study showed that a clonogenic,  rapidly proliferative population of cells existed in Beagle's apical papilla, and these cells had a significantly higher colony-forming rate than the stem cells  from apical papilla derived from humans (P<0.001). These cells had multilineage differentiation ability including osteogenic, adipogenic and chondrogenic  potentials. Mineralized nodules were formed after osteogenic induction, lipid droplets were found after adipogenic induction, and the pellets showed  positive immunohistochemical staining for collagen II after chondrogenic induction. These cells also expressed the mesenchymal stem cell markers  including STRO-1 and CD146, while negative for CK. Moreover, these cells transplanted with hydroxyapatite in immunocompromised mice could form  mineral tissue and pulp-dentin complex-like tissue.
  
  
  CONCLUSIONS
  There are stem cells from the apical papilla which have high proliferation ability and  multilineage differentiation potential existing in the Beagle's apical papilla.
authors.affiliation: Department of Pediatric Dentistry, Peking University School and Hospital of Stomatoloy, Beijing, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Yang
authors.forename: Yu-ming
authors.initials: YM
authors.lastname: Zhao
authors.forename: Wen-jun
authors.initials: WJ
authors.lastname: Wang
authors.forename: Wei-qian
authors.initials: WQ
authors.lastname: Jia
authors.forename: Li-hong
authors.initials: LH
authors.lastname: Ge
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003771:Dental Papilla / Q000166:cytology*; D004285:Dogs; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000378:metabolism; D016513:Mice, SCID; D010486:Periapical Tissue / Q000166:cytology*; D023822:Tissue Engineering