STIMULATION OF INTERLEUKIN-6 PRODUCTION OF PERIODONTAL-LIGAMENT CELLSBY PORPHYROMONAS-ENDODONTALIS LIPOPOLYSACCHARIDE

Interleukin-6 (IL-6), which is a multifunctional cytokine, has importa nt roles in acute and chronic inflammation and may also be implicated in bone resorption. We examined the IL-6 production in periodontal lig ament (PDL) cells which were treated with lipopolysaccharide (LPS) fro m several oral inflammatory pathogens. The LPS from Porphyromonas endo dontalis, which was isolated from infected root canals and radicular c yst fluids, was more potent than the LPS from any other periodontal or ganisms examined. P. endodontalis LPS stimulated IL-6 release from PDL cells in a time- and dose dependent manner. Northern blot hybridizati on analysis revealed that the IL-6 mRNA level in PDL cells was increas ed by P. endodontalis LPS. These results suggest that stimulation of t he IL-6 release of PDL cells by P. endodontalis LPS may have a role in the progression of inflammation and alveolar bone resorption in perio dontal and periapical diseases. (C) 1994 Academic Press, Inc.