Abstract:

Objective To investigate the relation of high mobility group box-1 protein（HMGB1）expression and cell apoptosis of synovial tissue with disease activity parameters in rheumatoid arthritis（RA）patients. Methods TUNEL apoptosis assay and immunochemistry analysis were used to determine HMGB1 expression and cell apoptosis of synovial tissue in RA patients（12 cases）and osteoarthritis（OA） patients（12 cases）. Immune rate scatter nephelometry,enzyme-linked immunosorbent assay（ELISA）and infrared barrier method were performed to determine serum C-reactive protein（CRP）,rheumatoid factor（RF）,anti-cyclic citrullinated peptide （CCP）antibody and erythrocyte sedimentation rate（ESR）of the 2 groups. Results The differences for age and sex between RA and OA groups were not statistically significant（P>0.05）. CRP,RF,anti-CCP antibody and ESR were significantly higher in RA group than those in OA group（P<0.01）. HMGB1 expression in synovial tissue was significantly higher in RA group than those in OA group（P<0.01）,and the cell apoptosis of synovial tissue was significantly lower in RA group than that in OA group（P<0.01）. The score of cell apoptosis in RA group was negatively correlated with CRP,ESR,anti-CCP antibody and RF（r=-0.628,-0.815,-0.783 and-0.757,P<0.05）,and HMGB1 expression score was positively correlated with CRP,ESR,anti-CCP antibody and RF（r=0.638,0.739,0.698 and 0.648,P<0.05）. Conclusions HMGB1 expression in RA group might affect the disease activity of RA by regulating cell apoptosis.

Key words: High mobility group box-1 protein, Apoptosis, Rheumatoid arthritis, Synovial tissue