Porphyromonas gingivalis Protease Degrades Cell Adhesion Molecules of Human Gingival Fibroblasts

Abstract: Porphyromonas gingivalis (P. gingivalis), one of the most probable pathogens of periodontal disease, produces several proteases, some of which are generally considered to be pathogenic although details of the mechanism of pathogenesis are still unknown. We analyzed the effect of the purified protease of P. gingivalis on a group of cell adhesion molecules including intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), very late antigen4 (VLA-4), and fibronectin in human gingival fibroblasts (HGF). Confluent monolayer cultures of HGF were incubated for 24 h with P. gingivalis protease. The amounts of ICAM-1, VCAM-1, VLA-4 and fibronectin were analyzed before and after the incubation by flow cytometric analysis of the HGF bound to FITC-conjugated monoclonal antibody. All the cell adhesion molecules examined became immunologically undetectable after 24 h incubation with P. gingivalis protease. These results suggest that degradation of the cell adhesion molecules by the P. gingivalis protease is one of the earliest invasive attacks in periodontal diseases caused by P. gingivalis.