The effects of epithelial rest of Malassez’ cells on interleukin-1β and interleukin-6 mRNA expression by periodontal ligament fibroblasts stimulated with sonicated Porphyromonas gingivalis in vitro

ObjectiveThe purpose of this study was to evaluate the effects of epithelial rest of Malassez’ (ERM) cells on interleukin (IL)-1β and IL-6 mRNA expression by periodontal ligament (PDL) fibroblasts in the presence of LPS using a co-culture technique.Materials and methodsERM cells plated in chambers on 0.4 μm pore membranes were placed in wells with PDL fibroblasts, and then were stimulated with sonicated Porphyromonas gingivalis (P.g.) for 6 and 24 h. PDL fibroblasts were then evaluated for mRNA and protein expression of IL-1β and IL-6.ResultsIL-1β and IL-6 mRNA expression by PDL fibroblasts increased from 6 to 24 h. IL-1β and IL-6 mRNA expression by PDL fibroblasts cultured with sonicated P.g. and ERM cells at 24 h was significantly higher than by PDL fibroblasts cultured without sonicated P.g. or ERM cells and PDL fibroblasts cultured with sonicated P.g. without ERM. Staining for IL-1β and IL-6 was positive around the nuclei. The expression of both IL-1β and IL-6 by PDL fibroblasts cultured with sonicated P.g. and ERM cells was higher than PDL fibroblasts cultured with sonicated P.g. without ERM cells.ConclusionsThis study indicates that ERM cells increase IL-1β and IL-6 expression by PDL fibroblasts in the presence of LPS.