Primus F J, Kelley E A, Hansen H J, Goldenberg D M
Center for Molecular Medicine and Immunology, University of Medicine and Dentistry of New Jersey, Newark 07103.
Clin Chem. 1988 Feb;34(2):261-4.
Measurements of carcinoembryonic antigen (CEA) in blood increased dramatically in some patients who were receiving injections of monoclonal antibody. CEA titers were measured with a monoclonal antibody-based double-determinant enzyme immunoassay in which untreated plasma specimens were diluted with an equal volume of buffer containing mouse serum. Increasing CEA titers were accompanied by the appearance and coincident increase in titers of human antibody against mouse Ig (HAMA). Adsorption of these sera with solid-phase anti-human IgG or Protein A restored antigen titers to pretreatment values; evidently the serum factor eliciting false-positive CEA titers was most probably HAMA. Neither addition of undiluted mouse serum to the assay mixture nor pretreatment by heating plasma specimens to 70 degrees C effectively abolished HAMA interference. By contrast, protein precipitation with polyethylene glycol (130 g/L) or heating plasma samples to 90 degrees C eliminated false-positive titers caused by HAMA, but did not reduce authentic CEA titers.
在一些接受单克隆抗体注射的患者中，血液中癌胚抗原（CEA）的测量值急剧增加。使用基于单克隆抗体的双决定簇酶免疫测定法测量CEA滴度，其中未处理的血浆标本用等体积含小鼠血清的缓冲液稀释。CEA滴度的增加伴随着抗小鼠Ig的人抗体（HAMA）滴度的出现和同时增加。用固相抗人IgG或蛋白A吸附这些血清可使抗原滴度恢复到预处理值；显然，引起CEA假阳性滴度的血清因子很可能是HAMA。向测定混合物中添加未稀释的小鼠血清或通过将血浆标本加热至70℃进行预处理均不能有效消除HAMA干扰。相比之下，用聚乙二醇（130 g/L）进行蛋白质沉淀或将血浆样品加热至90℃可消除由HAMA引起的假阳性滴度，但不会降低真实的CEA滴度。
