Ali A, Ali R
J Immunol Methods. 1983 Feb 11;56(3):341-6. doi: 10.1016/s0022-1759(83)80023-4.
An enzyme-linked immunosorbent assay is described for the assay of anti-DNA antibodies. The method employs plastic surface for immobilization of the antigen and alkaline phosphatase-linked rabbit anti-human IgG for the detection of immune complex using PNP-P and 4MU-P as substrates. The sensitivity of the assay increased by as much as 16-fold when fluorogenic substrate was used instead of conventional PNP-P and could therefore be employed for the detection of low avidity antibodies. Using PNP-P as substrate 57% of SLE patients were positive for DNA antibody, but if 4MU-P was introduced as substrate, 71% gave a positive response. Moreover, using a fluorogenic substrate, it was possible to minimise the amount of antigen (2 nM bp). The technique is simple, reproducible and of high sensitivity.
本文描述了一种用于检测抗DNA抗体的酶联免疫吸附测定法。该方法采用塑料表面固定抗原，并使用碱性磷酸酶标记的兔抗人IgG，以PNP-P和4MU-P作为底物检测免疫复合物。当使用荧光底物代替传统的PNP-P时，该测定法的灵敏度提高了多达16倍，因此可用于检测低亲和力抗体。以PNP-P为底物时，57%的SLE患者DNA抗体呈阳性，但如果引入4MU-P作为底物，则71%的患者呈阳性反应。此外，使用荧光底物可以将抗原量（2 nM碱基对）降至最低。该技术简单、可重复且灵敏度高。
