ABSTRACT
Bone sialoprotein [BSP] was quantified in synovial fluids and sera from rheumatoid arthritis [RA] patients to elucidate whether its release from bone relates to the degree of joint tissue destruction. BSP levels were determined by immunoassays of knee synovial fluids and of sera from 60 RA patients who were classified into 4 groups on the basis of radiographic knee joint tissue damage. Serum levels were compared with 15 matched healthy subjects as a control group. Synovial fluid concentrations of BSP increased with increasing degree of knee joint damage [F=13.5 and P<0.001]. Serum concentrations of BSP were increased above normal [t=5.9 and P<0.001]. but did not relate to the degree of joint damage [F=0.02 and P>0.05]. From these results we concluded that quantification of BSP in the synovial fluid can be useful as a mean for assessing the degree of tissue damage at the molecular level in patients with RA