ABSTRACTPorphyromonas gingivalis, a major periodontal pathogen, may contribute to atherogenesis and other inflammatory cardiovascular diseases. However, little is known about interactions betweenP. gingivalisand endothelial cells. E-selectin is a membrane protein on endothelial cells that initiates recruitment of leukocytes to inflamed tissue, and it may also play a role in pathogen attachment. In the present study, we examined the role of E-selectin inP. gingivalisadherence to endothelial cells. Human umbilical vein endothelial cells (HUVECs) were stimulated with tumor necrosis factor alpha (TNF-α) to induce E-selectin expression. Adherence ofP. gingivalisto HUVECs was measured by fluorescence microscopy. TNF-α increased adherence of wild-typeP. gingivalisto HUVECs. Antibodies to E-selectin and sialyl Lewis X suppressedP. gingivalisadherence to stimulated HUVECs.P. gingivalismutants lacking OmpA-like proteins Pgm6 and -7 had reduced adherence to stimulated HUVECs, but fimbria-deficient mutants were not affected. E-selectin-mediatedP. gingivalisadherence activated endothelial exocytosis. These results suggest that the interaction between host E-selectin and pathogen Pgm6/7 mediatesP. gingivalisadherence to endothelial cells and may trigger vascular inflammation.