Grant: Operating Grant

Most of the disabling consequences of chronic inflammatory joint diseases are the result of damage to the joints and surrounding cartilage and bone. Pathological local bone resorption associated with immune arthritis like rheumatoid or psoriatic arthritis, crystal-induced arthritis, and chronic infection of joints and bones, remains a major medical problem implicating enormous socio-economic costs. Etiology and initiating events of these inflammatory arthritis are unknown and our knowledge dealing with the tissue degrading process during inflammation remains too fragmentary. In recent years, factors of intercellular communication have been the subject of intense research which is promoting an increasing number of mediators involved in the inflammatory process. Among the numerous factors, osteoprotegerin, osteoprotegerin ligand and its receptor RANK are substances of particular interest since they appear to be involved in bone resorption and inflammation and they are targets for pharmacological modulation. A goal of the present study will be to evaluate the role of neutrophils through their expression of these compounds in bone resorption related to chronic arthritis.