Changes in serum levels of soluble osteoclast-associated receptor in human rheumatoid arthritis

Background Osteoclast-associated receptor （OSCAR） is a member of the newly identified leukocyte receptor complex,and has recently been described as a key molecule in osteoclastogenesis. In this study, we measured the levels of soluble osteoclast-associated receptor （sOSCAR） in the serum of rheumatoid arthritis （RA） patients and healthy controls to examine whether sOSCAR may play a role in the process of inflammatory arthritis.Methods Enzyme-linked immunosorbent assay （ELISA） was used to measure the levels of sOSCAR in the serum of 40 healthy controls and 40 RA patients.Results The serum levels of sOSCAR were significantly lower in RA patients than in healthy controls, and were inversely associated with inflammatory activity.Conclusion sOSCAR is decreased in patients with RA and reduced levels of the protein are associated with increased inflammatory response.