Effect of cysteine protease of Porphyromonas gingivalis on adhesion molecules in gingival epithelial cells.

We examined the effect of cysteine protease of Porphyromonas gingivalis (P. gingivalis) on cell adhesion molecules including intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and very late antigen-4 (VLA-4) of human gingival epithelial cells. The cells were incubated for 48 hr with or without P. gingivalis protease. Their cell adhesion molecule expression levels were increased at 12 hr, but decreased at 18-48 hr. This result suggests that protease degrades cell adhesion molecules. After the stimulation with protease for 12 hr, P. gingivalis fimbrial binding to a monolayer of the cells was effectively inhibited by the addition of the cell adhesion molecules, suggesting the fimbrial binding to the cells occurred through cell surface adhesion molecules.