S100A4 is expressed in human odontoblasts and odontoblast-like cells

Introduction: The calcium-binding protein S100A4 has been found in fibroblasts in many tissues. It has been well studied in the regulating process of inflammation and tumor metastasis. However, as a calcium regulating protein, its expression in the dental pulp has not yet been elucidated. The aim of this study was to investigate the in situ expression of S100A4 in dental pulp tissue.

Methods: Five intact and three carious human teeth were collected and sectioned. Hematoxylin and eosin (HE) staining was used to locate areas reflecting the characteristics of the tooth. Based on this initial evaluation, the slides adjacent to these areas were immunohistochemically stained with S100A4 and dentin sialophosphoprotein (DSPP) antibodies.

Results: In both the crown and root, S100A4 staining was observed in the odontoblast layer and in odontoblast-like cells, but not in other pulp cells. In contrast, DSPP was expressed in most cells of the dental pulp.

Conclusion: S100A4 is expressed in the odontoblast layer and in odontoblast-like cells in mature human pulp tissue. This protein can be used as a marker to differentiate these two kinds of cells from pulp cells.