Nordfang O, Høier-Madsen M, Danielsen A
Scand J Rheumatol. 1984;13(3):257-64. doi: 10.3109/03009748409100395.
IgM and IgG rheumatoid factors (RFs) were purified by affinity chromatography and gel filtration. The preparations thus obtained were used as standards in a radio-immunoassay for RF detection. In this assay, RFs were reacted with immunoprecipitates, and the RFs were detected with radiolabelled (F(ab')2 fragments specific for human IgM or IgG. The reproducibility of the assay was higher when RF content was expressed relative to the standards and not directly relative to tracer binding. It was found that the presence of IgM RF did not affect the measurement of IgG RF in this RIA, since the addition of neither mono- nor polyclonal IgM RF to a donor serum resulted in increased IgG RF measurements. 100 sera were analysed and were consistently positive in only one of the tests: sheep cell agglutination or latex fixation. The 75% of the sera which were positive only in the latex fixation test were positive for IgM RF in the radio-immunoassay, indicating that RFs in this type of serum were not specific solely for human IgG.
通过亲和层析和凝胶过滤法纯化IgM和IgG类风湿因子（RFs）。将由此获得的制剂用作放射免疫测定中检测RF的标准品。在该测定中，RFs与免疫沉淀物反应，并用针对人IgM或IgG的放射性标记（F(ab')2片段检测RFs。当RF含量相对于标准品表达而非直接相对于示踪剂结合表达时，该测定的重现性更高。发现在该放射免疫测定中IgM RF的存在不影响IgG RF的测量，因为向供体血清中添加单克隆或多克隆IgM RF均未导致IgG RF测量值增加。分析了100份血清，这些血清仅在一项检测中呈持续阳性：绵羊细胞凝集试验或乳胶凝集试验。仅在乳胶凝集试验中呈阳性的血清中有75%在放射免疫测定中IgM RF呈阳性，表明这类血清中的RF并非仅对人IgG具有特异性。
