妊娠相关血浆蛋白A酶联免疫诊断方法学研究

目的建立供临床检测妊娠相关血浆蛋白A（PAPP—A）的酶联免疫诊断方法。方法用足月孕妇血清通过分子筛以及离子交换层析纯化后制备抗体，进而制备生物素标记的PAPP—A以及酶标记抗体。按照常规的酶联免疫吸附试验（ELISA）操作步骤检测标本，观察本方法的敏感性、特异性、回收率、稳定性等指标。测定30份早孕患者血清与美国DRG公司试剂盒做对比。结果分子筛与离子交换层析纯化效果良好。标准曲线范围为1，50μg/mL。敏感性为0．35μg/mL，回收率均〉100％，特异性、稳定性试验结果显示效果良好。本试验方法与美国DRG公司试剂盒检测结果高度相关，回归方程为：Y=2．2861＋1．0269X（r=0．982，P〈0．01）。结论PAPP—A抗体标记生物素后，利用生物素与亲和素的高度亲和力进行ELISA，该方法在PAPP-A的临床检测中有较大的实际意义。

Study on the determination of pregnancy associated plasma protein A by ELISA

Objective To establish a enzyme-linked immunosorbent assay （ELISA） for the diagnosis method of pregnancy associated plasma protein （PAPP-A）. Methods Sera from full-term pregnant women were purified by molecular sieve and ion exchange chromatography, and then the biotin labeling PAPP-A and enzyme-labelled PAPP-A antibody were prepared. Traditional ELISA was used to detect the samples, and the sensitivity, specificity, recovery and stability were observed. The results of 30 samples from first trimester pregnant women were kit from DRG of USA. Results The result of the purification by molecular sieve and ion exchange chromatography was good. The range of standard curve was 1 - 50 p,g/mL. The sensitivity was 0.35 ~g/mL, the recovery was 〉 100% , and the stability and specificity were good. The method had good correlation with the kit from DRG of USA, and the regression equation was Y = 2. 286 1 ＋ 1. 026 9X（ r = 0. 982, P 〈 0.01 ）. Conclusions Biotin labeling PAPP-A is made, and the connection ability of biotin and avidin can be reflected in the ELISA. The ELISA is meaningful in the determination of PAPP-A.