Kay J, Austen K F, Czop J K
Department of Medicine, Harvard Medical School, Boston, MA.
Arthritis Rheum. 1991 Jun;34(6):687-96. doi: 10.1002/art.1780340609.
A cofactor that selectively opsonizes particulate activators of the human alternative complement pathway and enhances their phagocytosis by human monocytes was identified in synovial fluids of patients with rheumatoid arthritis. The active material was present in fluids treated with protease inhibitors, was heat stable, and was unaffected by incubation with hyaluronidase. Chromatographic isolation of synovial fluid fibronectin by gelatin affinity and by immunoaffinity on antifibronectin monoclonal antibody BD4 yielded similar quantities of protein for each of 3 fluids. Synovial fluid proteins with the BD4 fibronectin epitope accounted for essentially all of the phagocytosis-enhancing activity and expressed this activity by opsonizing target activators. Additional chromatographic analyses of synovial fluid fibronectin with the BD4 epitope were carried out using Sepharose-bearing gelatin and 4 additional antifibronectin monoclonal antibodies. The opsonic materials were characterized as having 2 distinct fibronectin epitopes, which always mapped from the cell adhesive domain to the carboxyl-terminus of plasma fibronectin, but only rarely contained the gelatin binding domain.
在类风湿性关节炎患者的滑液中发现了一种辅因子，它能选择性地调理人替代补体途径的颗粒性激活剂，并增强人单核细胞对它们的吞噬作用。活性物质存在于用蛋白酶抑制剂处理过的液体中，具有热稳定性，并且与透明质酸酶一起孵育时不受影响。通过明胶亲和色谱法和抗纤连蛋白单克隆抗体BD4的免疫亲和色谱法对滑液纤连蛋白进行分离，对于3种液体中的每一种，得到的蛋白量相似。具有BD4纤连蛋白表位的滑液蛋白基本上占了所有的吞噬增强活性，并通过调理靶激活剂来表达这种活性。使用带有明胶的琼脂糖和另外4种抗纤连蛋白单克隆抗体对具有BD4表位的滑液纤连蛋白进行了额外的色谱分析。调理物质的特征是具有2个不同的纤连蛋白表位，它们总是从细胞粘附结构域映射到血浆纤连蛋白的羧基末端，但很少含有明胶结合结构域。
