title: Ultrastructural localisation of TGF-beta exposure in dentine by chemical treatment.
abstract: Transforming growth factor-beta (TGF-beta) sequestered in dentine matrix has an important role in dental tissue repair after injury and its exposure at sites of injury may stimulate tertiary dentinogenesis. This study aimed to investigate the expression of TGF-beta isoforms in mature human dentine matrix and the ability of chemical treatments to expose TGF-beta on the cut surface of dentine using gold immunolabelling and subsequent scanning electron microscopy examination. TGF-beta1 was the only isoform that could be detected in human dentine and the nature of the chemical treatment of the tissue influenced its detection. EDTA treatment provided good exposure of TGF-beta1 on the dentine surface, whilst citric acid and sodium hypochlorite treatments revealed lesser amounts of this isoform. Only minimal staining for TGF-beta1 was observed in samples treated with phosphate-buffered saline. TGF-beta2 and -beta3 could not be detected in the specimens with any of the treatments. This study suggests that TGF-beta1 is the only TGF-beta isoform expressed by human odontoblasts to be sequestered in dentine implying that differences in isoform-extracellular matrix interactions may exist. Information on chemical treatment of tissue specimens for immunostaining may provide a useful basis for selection of tissue preparation techniques for clinical restorative treatment procedures to facilitate TGF-beta mediated reparative processes at sites of dental injury.
authors.affiliation: Conservative Dentistry, School of Stomatology, The Fourth Military Medical University, Xian, Peoples Republic of China.
authors.forename: S
authors.initials: S
authors.lastname: Zhao
authors.forename: A J
authors.initials: AJ
authors.lastname: Sloan
authors.forename: P E
authors.initials: PE
authors.lastname: Murray
authors.forename: P J
authors.initials: PJ
authors.lastname: Lumley
authors.forename: A J
authors.initials: AJ
authors.lastname: Smith
mesh_terms: D019343:Citric Acid; D003804:Dentin / Q000378:metabolism* / Q000648:ultrastructure; D004492:Edetic Acid; D006801:Humans; D008854:Microscopy, Electron; D008963:Molar / Q000378:metabolism; D020033:Protein Isoforms / Q000032:analysis / Q000187:drug effects / Q000378:metabolism; D012973:Sodium Hypochlorite; D016212:Transforming Growth Factor beta / Q000032:analysis* / Q000187:drug effects / Q000378:metabolism
chemical_list: D020033:Protein Isoforms; D016212:Transforming Growth Factor beta; D019343:Citric Acid; D004492:Edetic Acid; D012973:Sodium Hypochlorite