Distribution of Epithelial Cells and Their Relationship to Immunocompetent Cells in Rat Molars: A Confocal and Transmission Electron Microscope Study

Abstract

This study sought to investigate the distribution of cytokeratin (CK)-immunopositive cells and their relationship to immunocompetent ED1- and OX6-immunopositive cells in rat periodontium by immunohistochemistry and electron microscopy. CK-immunopositive cells were generally distributed along the surface of the tooth root. They could also be found between root dentin and cementum, in the perivascular space, and close to or in the alveolar bone lacunae. ED1-immunopositive cells exhibited a compact shape with small processes and were widely distributed in the periodontium. Few sections demonstrated an intimate relationship between the CK- and ED1-immunopositive cells close to the cementum, in the perivascular space, and close to or in the alveolar bone. Numerous OX6-immunopositive cells with long branching processes were widely distributed in the periodontal ligament, surrounding and holding CK-immunopositive cells in the cell clusters, close to the cementum. Transmission electron microscopy revealed OX6-immunopositive cells that extended their cytoplasmic processes, which contained vesicles and occasionally lysosomes in between the epithelial cells. This study demonstrates the close relationship between the epithelial cells and the immunocompetent cells in a rat periodontium, indicating a functional interrelationship. It is possible that in a non-inflammatory periodontium, the epithelial cells act not independently, but through interaction with immunocompetent cells.

Epithelial and PGP9.5-immunoreactive cells of Malassez epithelium in the periodontal ligament of cats: a transmission electron microscopic study

“…In the present study, blood vessels were sometimes observed close to the ME cells. Similar findings have been reported in previous studies [18,24]. In such areas, immunocompetent cells are close to or in contact with the ME cells [18].…”

“…Similar findings have been reported in previous studies [18,24]. In such areas, immunocompetent cells are close to or in contact with the ME cells [18]. However, the present study did not focus on the relationship between them.…”

“…Similar findings of cytoplasmic processes extending towards the outer surface of the ME and periodontal immunocompetent cells have been reported [17,18]. This morphology resembles that of sensory epithelial cells in glandular tissue, or the intestinal lumen.…”

“…Two different cell types, epithelial and cored vesicles contained cells, are composed of the ME in the PDL. cells has been reported in the rat PDL [17,18]. In the present study, blood vessels were sometimes observed close to the ME cells.…”

“…In the PDL, immunocompetent cells are known to be present widely and abundantly [18,22,23]. A close relationship between ME and immunocompetent Figure 3.…”