title: Expression of the IGF-1, IGFBP-3 and IGF-1 receptors in dental pulp stem cells and impacted third molars.
abstract: IGF-1 regulates the metabolism of hard dental tissue through binding to the IGF-1 receptor on target cells. Furthermore, IGF-binding-protein-3 promotes the accessibility of IGF-1. The aim of this study was to investigate the expression of IGF-1, IGFBP-3 and IGF-1R in STRO-1-positive dental pulp stem cells (DPSCs) and fully impacted wisdom teeth in relation to tooth development. Third molars were surgically removed from 60 patients and classified into two groups: teeth showing ongoing development (group 1) and teeth that had completed root shaping (group 2). The transcript and protein levels of IGF-1, IGFBP-3 and IGF-1R were investigated using RT-PCR and immunohistochemistry. The expression of the same proteins was also analyzed in DPSCs. The teeth from group 1 showed significantly stronger expression of IGF-1 and IGF-1R. The major sources of all of the proteins investigated immunohistochemically in sections of wisdom teeth were odontoblasts, cementoblasts and cell colonies in the pulpal mesenchyme. These colonies were identified as stem cells in view of their positivity for STRO-1, and the cells were subsequently sorted by flow cytometry. These DPSCs demonstrated high levels of pluripotency markers and IGF-1 and IGF-1R. We conclude that members of the IGF-1 family are involved in the late stage of tooth development and the process of pulpal differentiation.
authors.affiliation: Department of Operative Dentistry and Periodontology, University School of Dental Medicine, Faculty of Medicine, Martin-Luther-University of Halle-Wittenberg.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Magnucki
authors.forename: Ulf
authors.initials: U
authors.lastname: Schenk
authors.forename: Stefan
authors.initials: S
authors.lastname: Ahrens
authors.forename: Alexander
authors.initials: A
authors.lastname: Navarrete Santos
authors.forename: Christian R
authors.initials: CR
authors.lastname: Gernhardt
authors.forename: Hans-Günter
authors.initials: HG
authors.lastname: Schaller
authors.forename: Cuong
authors.initials: C
authors.lastname: Hoang-Vu
mesh_terms: D001483:Base Sequence; D015153:Blotting, Western; D002454:Cell Differentiation; D017931:DNA Primers; D003782:Dental Pulp / Q000166:cytology / Q000378:metabolism*; D005434:Flow Cytometry; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000378:metabolism*; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008964:Molar, Third / Q000378:metabolism* / Q000473:pathology; D017526:Receptor, IGF Type 1 / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013234:Stem Cells / Q000378:metabolism*; D014095:Tooth, Impacted / Q000378:metabolism*
chemical_list: D017931:DNA Primers; C583557:IGF1 protein, human; C515497:IGFBP3 protein, human; D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I; D017526:Receptor, IGF Type 1