Abstract
To investigate whether the expression of human leukocyte antigen-DR (HLA-DR) in synovial tissues obtained at synovectomy contributes to the clinical features of patients with rheumatoid arthritis (RA), immunohistochemical analysis was performed to determine the intensity and pattern of HLA-DR expression in synovial tissue from 96 patients with RA. The clinical features before and 1 year after the synovectomy were investigated. At the time of the surgery, duration of morning stiffness was associated with the degree of HLA-DR expression in synovial lining layer, and this synovial lining expression of HLA-DR was more frequently observed in elbow and wrist joints than in knee joint. In patients who underwent knee synovectomy, erythrocyte sedimentation rate and C-reactive protein level one year after the surgery were significantly higher in the patients with intense expression of HLA-DR in the synovial lining. Our findings showed that the expression of HLA-DR in the synovial lining contributes to several clinical features, and the expression in large joint such as knee may related with disease course of patients with RA.