类风湿因子引起抗双链DNA IgG抗体水平假性升高的探讨

A Study on False Increases in Anti-Double-Stranded DNA IgGAntibody Concentrations Due to Rheumatoid Factor

目的探讨3例患者血清中类风湿因子(RF)对酶联免疫法(ELISA)检测抗双链DNA IgG抗体的干扰。方法采用ELISA法检测RF和抗双链DNA IgG抗体;通过连续稀释法证实干扰的存在,利用包被人IgG的RF乳胶颗粒,胎牛血清和聚乙二醇6000(PEG 6000)去除RF对抗双链DNA IgG抗体的干扰。结果患者血清中均检测出高滴度的RF。经RF乳胶颗粒,胎牛血清和PEG 6000处理后,患者血清的抗双链DNA IgG抗体水平均降至正常参考范围。结论RF或将引起ELISA法检测抗双链DNA IgG抗体的假阳性结果。

Objective To investigate the interference of RF in the measurement of anti-dsDNA IgG antibodies by enzyme-linked immunosorbent assay(ELISA)in three cases.Methods Anti-dsDNA IgG antibodies and rheumatoid factor(RF)were detected by ELISA.To explore the role of interference in anti-dsDNA IgG antibody measurements,several steps including serial dilutions,RF latex particles coated with human IgG,fetal bovine serum,and polyethylene glycol(PEG)6000 precipitation were conducted.Results High levels of RF were identified.The concentrations of anti-dsDNA IgG antibodies in plasma from three patients were reduced to the normal reference range when RF was removed by the treatment with RF latex particles,FCS,and PEG 6000.Conclusion RF may cause false-positive results in the measurement of anti-dsDNA IgG antibodies detected by ELISA.