Detection of low affinity autoantibodies like anti-amyloid antibodies by surface plasmon resonance analysis Detection of low affinity autoantibodies like anti-amyloid antibodies by surface plasmon resonance analysis

本研究的目的是建立一种检测低亲和力抗体的SPR分析方法(Biacore)。作为一个模型，抗淀粉样抗体，可能出现在AA-淀粉样变性中，类风湿性关节炎的主要并发症，被作为目标。在研究过程中，我们成功地建立了抗SAA的单抗，无论是抗鼠还是抗人抗体。特别是，在淀粉样变过程中SAA降解产生的针对AA羧基末端的抗体将为进一步研究AA-淀粉样变性的基础和临床方面提供有用的信息。为了用Biacore检测抗体，固定了抗AA抗体的传感器芯片依次与提取的淀粉样蛋白组织、患者血清和抗人免疫球蛋白反应。当使用抗SAA抗体而不是患者血清时，该系统起作用。因此，该系统本身能够应用于其他自身抗体的检测。然而，使用患者血清的试验未能检测到显著的抗体活性。提高灵敏度可能是下一个需要改进的问题。

The purpose of this study was the development of the method using SPR analysis(Biacore), which could detect low affinity antibodies. As a model, anti-amyloid antibodies, which might appear in AA-amyloidosis, the major complication in rheumatoid arthritis, were targeted. In the process of investigation, we succeeded in establishing monoclonal anti-SAA, either anti-mouse or anti-human, antibodies. Especially, an antibody specific to AA carboxyl-terminus generated from SAA degradation during amyloidogenic process must be useful for the further investigation in fundamental and clinical aspects in AA-amyloidosis. For antibody detection using Biacore, a sensor chip immobilized with anti-AA antibodies was reacted in order with extracted amyloid tissues, patient serum, and anti-human immunoglobulin. The system worked when anti-SAA antibodies were used instead of patient serum. Thus, the system itself is able to be applied for detection of other autoantibodies. However, the trails using patient sera failed to detect the significant antibody activity. To amplify the sensitivity may be the next problem to improve.