title: [The effect of insulin-like growth factor-I on the proliferation and alkaline phosphatase activity of human periodontal ligament cells under three-dimensional culture system].
abstract: OBJECTIVE
  To investigate the effect of insulin-like growth factor- I (IGF- I) on the proliferation and alkaline phosphatase (ALP) activity of human periodontal ligament cells (hPDLCs) under three-dimensional (3D) culture system.
  
  
  METHODS
  The hPDLCs were cultured from periodontium of human teeth by the outgrowth method. Rotary cell culture system (RCCS) was enrolled to set 3D culture system. Samples were set to four groups: Negative control group, positive control group (3D group, IGF-I group), and experimental group (3D with IGF- I group). Proliferation was tested with methylthiazolyl tetrazolium (MTT), and ALP activity was assayed by spectrophotometer at 1, 3, 5, 7 d respectively.
  
  
  RESULTS
  Compared with that of negative control group, cell proliferation increased significantly in 3D with IGF-I group since 3 d (P < 0.05). Besides, the cell proliferation of 3D with IGF-I group was significantly higher than that of 3D group (P < 0.05). ALP activity of 3D with IGF- I group was significantly higher than that of negative control group, and 3D group at 3, 5, 7 d (P < 0.05).
  
  
  CONCLUSIONS
  IGF-I significantly promotes the proliferation and ALP activity of hPDLCs under 3D culture system.
authors.affiliation: Military Postgraduate Medical College, General Hospital of PLA, Beijing 100853, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Zhong-Ying
authors.initials: ZY
authors.lastname: Niu
authors.forename: Chu-Hua
authors.initials: CH
authors.lastname: Tang
authors.forename: Bo
authors.initials: B
authors.lastname: Bao
authors.forename: Tian-Peng
authors.initials: TP
authors.lastname: Shi
authors.forename: Shao-Yan
authors.initials: SY
authors.lastname: Si
mesh_terms: D000469:Alkaline Phosphatase; D002454:Cell Differentiation; D049109:Cell Proliferation; D002478:Cells, Cultured; D006801:Humans; D007334:Insulin-Like Growth Factor I; D010513:Periodontal Ligament; D013002:Somatomedins
chemical_list: D013002:Somatomedins; D007334:Insulin-Like Growth Factor I; D000469:Alkaline Phosphatase