Heat Shock Proteins and Oral Diseases: Special Focus on Periodontitis

Abstract

Oral microorganisms colonising the gingival crevice elicit all inflammatory reaction. In most individuals this inflammation is functional, i.e. leads to chronic gingivitis, however in some cases the bacterial presence causes an aberrant inflammatory reaction which will also degrade the surrounding periodontal tissues (periodontitis). Heat shock proteins play an important role in gingivitis and periodontitis and there will be an ongoing consumption of heat shock proteins in the inflamed periodontal tissue due to the release of reactive oxygen species and proteases. There is currently much discussion regarding the relationship between periodontitis and atherosclerosis, since heat shock proteins are expressed on the cell surface on the periodontitis pathogen Porphyromonas gingivalis and it has been suggested that the expression of heat shock proteins and immunity to heat shock proteins is involved in the establishment and progression of cardiovascular disease. Furthermore, it has also been suggested that persons with periodontitis might have a deficiency in the ability to mount humoral responses to heat shock proteins. This could further promote the establishment of chronic inflammation. Heat shock proteins have also been associated with other temporo mandibular Joint disorders, as well as with oral mucosal lesions such as oral lichen planus. Heat shock proteins are present in human saliva and therefore important in the immune defence in the oral mucosa. It therefore appears that heat shock proteins are highly important in the immunological defence of the oral cavity, especially when the immune response is induced on oral mucosal surfaces. The importance of heat shock proteins in oral diseases and the relationship between oral disease and the systemic consequences thereof remain unclear. Further studies are clearly required. This chapter reviews the current literature in this area.