抗环瓜氨酸多肽(cyclic citrullinated peptide,CCP)抗体是类风湿关节炎(rheumatoid arthritis,RA)早期诊断的重要生物标志物.为了实现对RA的早期诊断,本研究建立了一种基于CdTe量子点标记技术检测抗CCP抗体的免疫荧光层析法.将CCP多肽与小牛血清白蛋白(bovineserumalbumin,BSA)连接,再将CCP—BSA和羊抗鼠IgG分别在硝酸纤维素膜(nitrocellulosemembrane,NC膜)上划线,作为检测线(testline,T线)和质控线(controlline,C线).制备量子点并在量子点上标记鼠抗人IgG,喷在玻璃纤维上并烘干,最后组装大卡、切割并封装制成检测试纸条.应用该试纸条检测了RA患者及健康人血清临床样本200份,以酶联免疫吸附测定法(enzyme—linkedimmunosorbentassay,ELISA)为对照,计算免疫荧光层析法的检测灵敏度和特异性.结果显示,建立的量子点免疫荧光层析试纸条检测抗CCP抗体的灵敏度为97.5%,特异性为95.8%.该方法操作简单、快速,可实现床旁检测(point-of—caretesting,POCT),能应用于RA的早期诊断.
Anti-cyclic citrullinated peptide antibody (anti-CCP antibody) is an important biomarker for early detection of rheumatoid arthritis (RA). For clinical diagnosis of RA in the early stage, an immunochromatographic test strip for anti-CCP antibody detection was developed based on quantum dots. First, CCP was linked to bovine serum albumin (BSA) ; and then, the CCP-BSA and goat anti-mouse IgG were dotted on the nitrocellulose membrane as test line (T line) and control line (C line), respectively. Subsequently, quantum dots solution was prepared and conjugated to the mouse anti-human IgG antibody; further more, the marked quantum dots were sprayed to the glass fibers and dried. Last, all components of immunoehromatographic test strip were assembled, cut and packaged. The test strip has been applied to the detection of 200 clinic serum samples from RA patients and healthy people, and the sensitivity and specificity of the test strip were calculated with enzyme-linked immunosorbent assay ( ELISA ) as the control. The results showed that the sensitivity and specificity of the immunochromatographic test strip were 97.5% and 95.8% , respectively, indicating that the test strip could be a powerful diagnostic tool for the early detection of RA with advantages of simplicity and high speed manipulation, and can be used in point-of-care testing (POCT).