Detection of IL-18 and IL-1β protein and mRNA in human oral epithelial cells induced by Campylobacter concisus strains.

Abstract

Campylobacter concisus is an emerging bacterial pathogen that may play a role in the development of inflammatory bowel disease and oral inflammatory conditions such as periodontal disease. To elucidate the role and pathogenic mechanisms of C.\xa0concisus in contributing to oral inflammation, this study examined the production of IL-1 family proinflammatory cytokines IL-18 and IL-1β in oral epithelial cells induced by C.\xa0concisus strains using enzyme-linked immunosorbent assay (ELISA), Western-blot and quantitative real-time PCR. C.\xa0concisus increased the mRNA levels of IL-18 and IL-1β in oral epithelial cells. Furthermore, a large amount of IL-18 in the supernatants of oral epithelial cells infected with C.\xa0concisus strains was detected by ELISA, and various experiments demonstrated that this positive signal was derived from C.\xa0concisus bacterium. The findings that C.\xa0concisus upregulated IL-18 and IL-1β in oral epithelial cells from this study support a role of C.\xa0concisus in oral inflammatory diseases. Furthermore, the finding that C.\xa0concisus released a molecule that was strongly cross-reactive to anti-human IL-18 monoclonal antibodies suggests that in future studies examining cytokines induced by bacterial microbes, a bacterium control should be included.