Itoh J, Nose M, Fujita T, Kato M, Ohyama A, Kyogoku M
Department of Pathology, Tohoku University School of Medicine, Sendai, Japan.
Clin Exp Immunol. 1991 Mar;83(3):364-8. doi: 10.1111/j.1365-2249.1991.tb05644.x.
Decay-accelerating factor (DAF), a membrane inhibitor of homologous complement activation, is present in synovial cells lining joint space and detected in synovial fluid. DAF is considered to protect synovial membrane from complement-mediated injury associated with articular inflammation. We studied the immunohistopathological features of DAF molecules in synovial membrane of rheumatoid synovitis using a DAF-specific monoclonal antibody, 1C6. Reacting molecules with the 1C6 antibodies in synovial tissue extracts formed a 70-kD band in Western blot analysis. DAF was strongly detected on the flat synovial lining cells, but weakly on the hyperplastic and multi-layered lining cells in rheumatoid synovitis. The latter cells reacted with anti-Leu-M3 antibodies specific for a cell surface marker of activated macrophages, sometimes accompanied by C3 and IgM deposition on the superficial synovial membrane. These results suggest that active rheumatoid synovitis characteristically with hyperplastic synovial lining cells is out of control by DAF, thereby permitting further complement-mediated injury.
衰变加速因子（DAF）是同源补体激活的膜抑制剂，存在于关节腔衬里的滑膜细胞中，并在滑液中被检测到。DAF被认为可保护滑膜免受与关节炎症相关的补体介导的损伤。我们使用DAF特异性单克隆抗体1C6研究了类风湿性滑膜炎滑膜中DAF分子的免疫组织病理学特征。在蛋白质印迹分析中，滑膜组织提取物中与1C6抗体反应的分子形成了一条70-kD的条带。在类风湿性滑膜炎中，扁平的滑膜衬里细胞上强烈检测到DAF，但在增生性和多层衬里细胞上则检测到较弱的信号。后者细胞与针对活化巨噬细胞的细胞表面标志物的抗Leu-M3抗体发生反应，有时伴有C3和IgM沉积在滑膜表面。这些结果表明，具有增生性滑膜衬里细胞的活动性类风湿性滑膜炎不受DAF的控制，从而允许进一步的补体介导的损伤。
