A cell line with characteristics of the periodontal ligament fibroblasts is negatively regulated for mineralization and Runx2/Cbfa1/Osf2 activity, part of which can be overcome by bone morphogenetic protein-2

Yoshinori Saito, Tatsuya Yoshizawa, Fumio Takizawa, Mika Ikegame, Osamu Ishibashi, Kazuhiro Okuda, Kohji Hara, Kotaro Ishibashi, Masuo Obinata, Hiroyuki Kawashima

Research output: Contribution to journalReview article

105 Citations (Scopus)


The periodontal ligament (PDL) is a connective tissue located between the cementum of teeth and the alveolar bone of the mandibula. It plays an integral role in the maintenance and regeneration of periodontal tissue. The cells responsible for maintaining this tissue are thought to be fibroblasts, which can be either multipotent or composed of heterogenous cell populations. However, as no established cell lines from the PDL are available, it is difficult to assess what type of cell promotes all of these functions. As a first step to circumvent this problem, we have cloned and characterized cell lines from the PDL from mice harboring a temperature-sensitive SV 40 large T-antigen gene. RT-PCR and in situ hybridization studies demonstrated that a cell line, designated PDL-L2, mimics the gene expression of the PDL in vivo: it expresses genes such as alkaline phosphatase, type I collagen, periostin, runt-related transcription factor-2 (Runx2) and EGF receptor, but does not express genes such as bone sialoprotein and osteocalcin. Unlike osteoblastic cells and a mixed cell population from the PDL, PDL-L2 cells do not produce mineralized nodules in the minearlization medium. When PDL-L2 cells were incubated in the presence of recombinant human bone morphogenetic protein-2 alkaline phosphatase activity increased and mineralized nodules were eventually produced, although the extent of mineralization is much less than that in osteoblastic MC3T3-E1 cells. Furthermore, PDL-L2 cells appeared to have a regulatory mechanism by which the function of Runx2 is normally suppressed.

Original languageEnglish
Pages (from-to)4191-4200
Number of pages10
JournalJournal of cell science
Issue number21
Publication statusPublished - Nov 1 2002
Externally publishedYes



  • BMP-2
  • Cell line
  • Mineralization
  • Periodontal ligament
  • Runx2/Cbfa1/Osf-2

ASJC Scopus subject areas

  • Cell Biology

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