title: Effects of HEMA and TEDGMA on the in vitro odontogenic differentiation potential of human pulp stem/progenitor cells derived from deciduous teeth.
abstract: OBJECTIVE
  The aim of this study was to investigate the effects of HEMA and TEGDMA on the odontogenic differentiation potential of dental pulp stem/progenitor cells.
  
  
  METHODS
  Dental stem/progenitor cell cultures were established from pulp biopsies of human deciduous teeth of 1-3 year-old children (Deciduous Teeth Stem Cells-DTSCs). Cultures were characterized for stem cell markers, including STRO-1, CD146, CD34, CD45 using flow cytometry. Cytotoxicity was evaluated with the MTT assay. DTSCs were then induced for osteo/odontogenic differentiation by media containing dexamethasone, KH(2)PO(4),β-glycerophosphate and L-ascorbic acid phosphate in the presence of nontoxic concentrations of HEMA (0.05-0.5mM) and TEGDMA (0.05-0.25mM) for 3 weeks. Additionally, the effects of a single exposure (72 h) to higher concentrations of HEMA (2mM) and TEGDMA (1mM) were also evaluated.
  
  
  RESULTS
  DTSCs cultures were positive for STRO-1 (7.53±2.5%), CD146 (91.79±5.41%), CD34 (11.87±3.02%) and negative for CD45. In the absence of monomers cell migration, differentiation and production of mineralized dentin-like structures could be observed. Cells also progressively expressed differentiation markers, including dentin sialophosphoprotein-DSPP, bone sialoprotein-BSP, osteocalcin-OCN and alkaline phosphatase-ALP. On the contrary, long-term exposure to nontoxic concentrations of HEMA and TEGDMA significantly delayed the differentiation and mineralization processes of DTSCs, whereas, one time exposure to higher concentrations of these monomers almost completed inhibited mineral nodule formation. BSP, OCN, ALP and DSPP expression were also significantly down-regulated.
  
  
  CONCLUSIONS
  These findings suggest that HEMA and TEGDMA can severely disturb the odontogenic differentiation potential of pulp stem/progenitor cells, which might have significant consequences for pulp tissue homeostasis and repair.
authors.affiliation: Department of Fixed Prosthesis & Implant Prosthodontics, School of Dentistry, Aristotle University of Thessaloniki, Greece.
authors.forename: Athina
authors.initials: A
authors.lastname: Bakopoulou
authors.forename: Gabriele
authors.initials: G
authors.lastname: Leyhausen
authors.forename: Joachim
authors.initials: J
authors.lastname: Volk
authors.forename: Asterios
authors.initials: A
authors.lastname: Tsiftsoglou
authors.forename: Pavlos
authors.initials: P
authors.lastname: Garefis
authors.forename: Petros
authors.initials: P
authors.lastname: Koidis
authors.forename: Werner
authors.initials: W
authors.lastname: Geurtsen
mesh_terms: D000469:Alkaline Phosphatase / Q000032:analysis; D018952:Antigens, CD34 / Q000032:analysis; D000954:Antigens, Surface / Q000032:analysis; D001205:Ascorbic Acid / Q000494:pharmacology; D015415:Biomarkers / Q000032:analysis; D051929:CD146 Antigen / Q000032:analysis; D002113:Calcification, Physiologic / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D002675:Child, Preschool; D003782:Dental Pulp / Q000166:cytology / Q000187:drug effects*; D003907:Dexamethasone / Q000494:pharmacology; D015536:Down-Regulation; D016326:Extracellular Matrix Proteins / Q000032:analysis; D005938:Glucocorticoids / Q000494:pharmacology; D005994:Glycerophosphates / Q000494:pharmacology; D006801:Humans; D007223:Infant; D058574:Integrin-Binding Sialoprotein / Q000032:analysis; D017493:Leukocyte Common Antigens / Q000032:analysis; D008689:Methacrylates / Q000494:pharmacology*; D009805:Odontogenesis / Q000187:drug effects*; D015675:Osteocalcin / Q000032:analysis; D010710:Phosphates / Q000494:pharmacology; D010750:Phosphoproteins / Q000032:analysis; D011092:Polyethylene Glycols / Q000494:pharmacology*; D011109:Polymethacrylic Acids / Q000494:pharmacology*; D017680:Potassium Compounds / Q000494:pharmacology; D012795:Sialoglycoproteins / Q000032:analysis; D013234:Stem Cells / Q000187:drug effects*; D014094:Tooth, Deciduous / Q000166:cytology*; D000099311:Dentin Sialophosphoprotein
chemical_list: D000469:Alkaline Phosphatase; D018952:Antigens, CD34; D000954:Antigens, Surface; D001205:Ascorbic Acid; D015415:Biomarkers; D051929:CD146 Antigen; D003907:Dexamethasone; D016326:Extracellular Matrix Proteins; D005938:Glucocorticoids; D005994:Glycerophosphates; D058574:Integrin-Binding Sialoprotein; D017493:Leukocyte Common Antigens; D008689:Methacrylates; D015675:Osteocalcin; D010710:Phosphates; D010750:Phosphoproteins; D011092:Polyethylene Glycols; D011109:Polymethacrylic Acids; D017680:Potassium Compounds; D012795:Sialoglycoproteins; D000099311:Dentin Sialophosphoprotein; C497902:MCAM protein, human; C525591:STRO-1 antigen, human; C020946:triethylene glycol dimethacrylate; C005044:hydroxyethyl methacrylate; C013216:potassium phosphate; C516769:PTPRC protein, human; C031463:beta-glycerophosphoric acid