MEDLINE Journals

    Quiescent epithelial cell rests of Malassez can differentiate into ameloblast-like cells.

    Shinmura Y, Tsuchiya S, Hata K, et al. 
    J Cell Physiol 2008 Dec; 217(3) :728-38.

    Epithelial cell rests of Malassez (ERM) are quiescent epithelial remnants of Hertwig's epithelial root sheath (HERS) that are involved in the formation of tooth roots. After completion of crown formation, HERS are converted from cervical loop cells, which have the potential to generate enamel for tooth crown formation. Cervical loop cells have the potential to differentiate into ameloblasts. Generally, no new ameloblasts can be generated from HERS, however this study demonstrated that subcultured ERM can differentiate into ameloblast-like cells and generate enamel-like tissues in combination with dental pulp cells at the crown formation stage. Porcine ERM were obtained from periodontal ligament tissue by explant culture and were subcultured with non-serum medium. Thereafter, subcultured ERM were expanded on 3T3-J2 feeder cell layers until the tenth passage. The in vitro mRNA expression pattern of the subcultured ERM after four passages was found to be different from that of enamel organ epithelial cells and oral gingival epithelial cells after the fourth passage using the same expansion technique. When subcultured ERM were combined with subcultured dental pulp cells, ERM expressed cytokeratin14 and amelogenin proteins in vitro. In addition, subcultured ERM combined with primary dental pulp cells seeded onto scaffolds showed enamel-like tissues at 8 weeks post-transplantation. Moreover, positive staining for amelogenin was observed in the enamel-like tissues, indicating the presence of well-developed ameloblasts in the implants. These results suggest that ERM can differentiate into ameloblast-like cells.

    3T3 Cells
    Cell Differentiation
    Cell Proliferation
    Cell Separation
    Cell Transplantation
    Cells, Cultured
    Dental Enamel
    Dental Pulp
    Epithelial Cells
    Gene Expression Regulation
    Periodontal Ligament
    Reverse Transcriptase Polymerase Chain Reaction
    Tooth, Deciduous


    Pub Type(s)
    Journal Article Research Support, Non-U.S. Gov't
    PubMed ID


    Content Manager
    Related Content

    Subcultured odontogenic epithelial cells in combination with dental mesenchymal cells produce enamel-dentin-like complex structures.

    Observations on continuously growing roots of the sloth and the K14-Eda transgenic mice indicate that epithelial stem cells can give rise to both the ameloblast and root epithelium cell lineage creating distinct tooth patterns.

    Dental follicle cells and cementoblasts induce apoptosis of ameloblast-lineage and Hertwig's epithelial root sheath/epithelial rests of Malassez cells through the Fas-Fas ligand pathway.

    Enamel tissue engineering using subcultured enamel organ epithelial cells in combination with dental pulp cells.

    Production of osteopontin by cultured porcine epithelial cell rests of Malassez.

    Production of amelogenin by enamel epithelium of Hertwig's root sheath.

    In vitro differentiation of epithelial cells cultured from human periodontal ligament.

    The Ca(2+)-binding protein calretinin is selectively enriched in a subpopulation of the epithelial rests of Malassez.