title: Mineralized nodule formation by human dental papilla cells in culture.
abstract: Human dental papilla cells were enzymatically separated from deciduous tooth germs of an 8-month-old embryo legally aborted. The second passage cells were cultured up to 35 days in 3 groups. The beta-GP group was cultured in the Dulbecco MEM containing ascorbic acid and beta-glycerophosphate supplemented with 15% fetal bovine serum. The Dex group was in the same medium, in addition containing dexamethasone. The control group contained none of the 3 chemicals. Mineralized nodules were formed after 15 days in the beta-GP and Dex groups. Only in the presence of ascorbic acid and organic phosphate did they mineralize. The addition of dexamethasone caused a significant increase in the number of nodules. By electron microscopy, the nodules contained needle-shaped crystals associated with a network of collagen fibrils. Calcium and phosphorus were detected by energy-dispersive X-ray microanalysis in the nodules. Furthermore, the crystalline material exhibited a pattern consistent with hydroxyapatite and dentin when examined by X-ray diffractometry. Cells showed high levels of alkaline phosphatase activity, which was increased 2-3 times in the presence of the 3 chemicals. These results indicated that human dental papilla cells have the ability to form dentin in culture. The formation of mineralized nodules by human dental papilla in vitro provides a useful model for studying the morphogenesis and differentiation of dental papilla ectomesenchyme.
authors.affiliation: Laboratory of Dental Pulp Biology, Qin Du Stomatological Hospital, XI'an, Shaanxi, PR China.
authors.forename: J
authors.initials: J
authors.lastname: Hao
authors.forename: S
authors.initials: S
authors.lastname: Shi
authors.forename: Z
authors.initials: Z
authors.lastname: Niu
authors.forename: Z
authors.initials: Z
authors.lastname: Xun
authors.forename: L
authors.initials: L
authors.lastname: Yue
authors.forename: M
authors.initials: M
authors.lastname: Xiao
mesh_terms: D000469:Alkaline Phosphatase / Q000032:analysis / Q000187:drug effects; D001205:Ascorbic Acid / Q000494:pharmacology; D002118:Calcium / Q000032:analysis; D002454:Cell Differentiation; D002478:Cells, Cultured; D003094:Collagen / Q000648:ultrastructure; D003461:Crystallography; D003470:Culture Media; D003771:Dental Papilla / Q000187:drug effects / Q000196:embryology / Q000502:physiology* / Q000648:ultrastructure; D003804:Dentin / Q000737:chemistry / Q000648:ultrastructure; D003810:Dentinogenesis; D003907:Dexamethasone / Q000494:pharmacology; D017886:Durapatite / Q000032:analysis; D004475:Ectoderm / Q000502:physiology; D004577:Electron Probe Microanalysis; D005938:Glucocorticoids / Q000494:pharmacology; D005994:Glycerophosphates / Q000494:pharmacology; D006801:Humans; D008297:Male; D008648:Mesoderm / Q000502:physiology; D008854:Microscopy, Electron; D009024:Morphogenesis; D010758:Phosphorus / Q000032:analysis; D014074:Tooth Calcification / Q000187:drug effects / Q000502:physiology*; D014083:Tooth Germ / Q000196:embryology; D014094:Tooth, Deciduous / Q000196:embryology; D014961:X-Ray Diffraction
chemical_list: D003470:Culture Media; D005938:Glucocorticoids; D005994:Glycerophosphates; D010758:Phosphorus; D003907:Dexamethasone; D003094:Collagen; D017886:Durapatite; D000469:Alkaline Phosphatase; D001205:Ascorbic Acid; D002118:Calcium; C031463:beta-glycerophosphoric acid