Oka H, Hirohata S, Inoue T, Iwamoto S, Miyamoto T
Department of Medicine and Physical Therapy, Faculty of Medicine, University of Tokyo, Japan.
Clin Chim Acta. 1990 Apr 30;188(2):147-59. doi: 10.1016/0009-8981(90)90159-p.
A method to standardize the quantitation of IgM-rheumatoid factor (RF) by enzymeimmunoassay (EIA) is presented. Serially diluted sera from rheumatoid arthritis patients were added to immobilized human IgG, and bound IgM-RF was detected by addition of horseradish peroxidase labeled anti-human IgM (HRPOaM). The concentration of IgM-RF which produced half of the maximal absorbance at 492 nm given by a saturating concentration of IgM-RF in the EIA plate, was defined as 1 U/ml. The IgM-RF values of test samples were measured as the dilution of the sample which provided half-maximal absorbance. The IgM-RF values determined by this method coincided with those determined by referring to a standard curve made from a serum containing known amounts of IgM-RF. Differences in IgM-RF values, which were caused by varying preparations of horseradish peroxidase anti-IgM (HRPOaM) were corrected for the binding capacity of each preparation to various concentrations of human IgM adherent to the plate. The IgM-RF values determined by this method correlated well with the RF values determined by latex photometric immunoassay (r = 0.956, p less than 0.001). IgM-RF values determined by EIA were converted into WHO-units by an empirical formula described. The data observed suggest that the method here reported can standardize IgM-RF values obtained by EIA.
本文介绍了一种通过酶免疫测定法（EIA）对IgM类风湿因子（RF）进行定量标准化的方法。将类风湿性关节炎患者的系列稀释血清加入固定化的人IgG中，并通过添加辣根过氧化物酶标记的抗人IgM（HRPOaM）来检测结合的IgM-RF。在EIA板中，使IgM-RF饱和浓度产生492nm处最大吸光度一半的IgM-RF浓度定义为1U/ml。测试样品的IgM-RF值以提供最大吸光度一半的样品稀释度来测量。通过该方法测定的IgM-RF值与通过参考由含有已知量IgM-RF的血清制成的标准曲线所测定的值一致。由不同制备的辣根过氧化物酶抗IgM（HRPOaM）引起的IgM-RF值差异，根据每种制剂对板上不同浓度人IgM的结合能力进行校正。通过该方法测定的IgM-RF值与通过乳胶光度免疫测定法测定的RF值相关性良好（r = 0.956，p < 0.001）。通过EIA测定的IgM-RF值通过所述经验公式转换为WHO单位。观察到的数据表明，本文报道的方法可以使通过EIA获得的IgM-RF值标准化。
