A virulence factor of Helicobacter pylori: role of heat shock protein in mucosal inflammation after H. pylori infection.

Among the various virulence factors of Helicobacter pylori the role of its heat shock protein 60 (HSP60, HspB) in mucosal inflammation after H. pylori infection was examined. In flow cytometric analysis, the expression of HSP60 on the cell surface was different, depending on the H. pylori strain used. The HSP60 epitope was also detected on the surface of both human gastric cancer cells (MKN45, KATOIII, and MKN28) and human gastric biopsy specimens. The intensity of the expression of HSP60 on the cell surface correlated significantly with the adhesion of H. pylori to MKN45 cells, but not with urease activity and production of vacuolating cytotoxin. A monoclonal antibody to H. pylori HSP60 inhibited the adhesion of H. pylori to MKN45 cells. These results suggest that HSP60 of H. pylori might act as an important virulence factor after H. pylori infection.