Human Gingival Epithelial Cells Produce Chemotactic Factors Interleukin-8 and Monocyte Chemoattractant Protein-1 After Stimulation With Porphyromonas gingivalis via Toll-Like Receptor 2

Background: The mechanism of stimulation of human gingival epithelial cells (HGEC) by Porphyromonas gingivalis (Pg) has not been fully clarified yet. In order to investigate the possible activation of HGEC by Pg through Toll-like receptors (TLRs), we analyzed the production of chemotactic factors and the activated nuclear factor-kappa B (NF-κB). Methods: The mRNA expression of TLRs and the protein expression of TLR2 and TLR4 in HGEC and gingival tissue were assessed using reverse transcription-polymerase chain reaction (RT-PCR) assay and immunohistochemical staining. Primary cultured HGEC (nHGEC) and HGEC transformed by simian virus 40 T antigen (OBA-9) were activated by a sonic extract (SE) of Pg to examine cytokine production and NF-κB activation using enzyme-linked immunosorbant assay (ELISA). In addition, Pg mediated activation of NF-κB in a TLR2-transfectant was also investigated. Results: RT-PCR results revealed that HGEC expressed mRNA of TLR2, TLR4, TLR5, and TLR9, although the expression pro- fil...