Invasion of human coronary artery cells by periodontal pathogens

There is an emerging paradigm shift from coronary heart disease having a pu rely hereditary and nutritional causation to possibly having an infectious etiology. Recent epidemiological studies have shown a correlation between p eriodontal disease and coronary heart disease. However, to date, there is m inimal information as to the possible disease mechanisms of this associatio n. It is our hypothesis that invasion of the coronary artery cells by oral bacteria may start and/or exacerbate the inflammatory response in atheroscl erosis. Since a few periodontal pathogens have been reported to invade oral epithelial tissues, we tested the ability of three putative periodontal pa hogens-Eikenella corrodens, Porphyromonas gingivalis, and Prevotella interm edia-to invade human coronary artery endothelial cells and coronary artery smooth muscle cells. In this study we demonstrate by an antibiotic protecti on assay and electron microscopy that specific species and strains invade c oronary artery cells at a significant level. Actin polymerization and eukar yotic protein synthesis in metabolically active cells were required since t he corresponding inhibitors nearly abrogated invasion. Many intracellular P . gingivalis organisms were seen to be present in multimembranous vacuoles resembling autophagosomes by morphological analysis. This is the first repo rt of oral microorganisms invading human primary cell cultures of the vascu lature.