Müller F, Moskophidis M, Borkhardt H L
Eur J Clin Microbiol. 1987 Feb;6(1):35-9. doi: 10.1007/BF02097187.
The indirect enzyme-linked immunosorbent assay (ELISA) for detection of immunoglobulin M (IgM) antibodies to Treponema pallidum in sera of syphilitic patients is complicated by false positive reactions due to the interference of IgM rheumatoid factor (IgM-RF) activity and the presence of treponemal IgG antibodies. Another source of error producing false negative results is the competition between treponemal IgG and IgM antibodies for the binding sites on the antigen. To avoid these complications in the indirect Treponema pallidum-specific IgM-ELISA, total IgG was immunoprecipitated from sera of syphilitic patients prior to the assay. The IgM-RF from non-precipitated sera reacted in an IgM-RF-ELISA and in the Treponema pallidum-IgM-specific ELISA with identical titers. After precipitation of total IgG no reaction of the IgM-RF in the assay could be demonstrated. Competition between IgG and IgM antibodies can be prevented almost completely by the precipitation procedure. The sensitivity and specificity of the Treponema pallidum-specific IgM-ELISA after immunoprecipitation of total serum IgG were shown to be higher than 97 percent.
用于检测梅毒患者血清中梅毒螺旋体免疫球蛋白M（IgM）抗体的间接酶联免疫吸附测定（ELISA），因IgM类风湿因子（IgM-RF）活性的干扰和梅毒螺旋体IgG抗体的存在而出现假阳性反应，使检测变得复杂。产生假阴性结果的另一个误差来源是梅毒螺旋体IgG和IgM抗体对抗原结合位点的竞争。为避免间接梅毒螺旋体特异性IgM-ELISA中出现这些复杂情况，在检测前从梅毒患者血清中免疫沉淀总IgG。未沉淀血清中的IgM-RF在IgM-RF-ELISA和梅毒螺旋体IgM特异性ELISA中的反应滴度相同。总IgG沉淀后，检测中未显示IgM-RF有反应。通过沉淀程序几乎可以完全防止IgG和IgM抗体之间的竞争。总血清IgG免疫沉淀后梅毒螺旋体特异性IgM-ELISA的敏感性和特异性均高于97%。
