Negoro N, Kanayama Y, Takeda T, Koda S, Inoue T
J Immunol Methods. 1986 Jul 11;91(1):83-9. doi: 10.1016/0022-1759(86)90105-5.
We developed a solid-phase radioimmunoassay for complement (C)-fixing nuclear ribonucleoprotein (nRNP):anti-nRNP immune complexes (nRNP ICs). The assay was based on the ability of the C-fixing nRNP ICs to bind strongly to immobilized F(ab')2 anti-C3. The extent of binding was quantified by incubating the C-fixing nRNP ICs bound to anti-C3 with 125I-labeled anti-nRNP-specific IgG. The interaction between anti-C3 and C-fixing nRNP ICs was rapid, time- and concentration-dependent and sensitive over a broad range of nRNP IC concentrations in an antigen-antibody ratio of 8 : 1 (9.8-5000 ng of human aggregated IgG equivalent per ml). We found that the assay also detected an immunoreactive U1-RNP antigen in Sm : anti-Sm immune complexes but did not detect SSA : anti-SSA immune complexes. The assay was preliminary applied for serum samples obtained from patients with mixed connective tissue disease (MCTD), and elevated concentrations of nRNP immune complexes were found in 3 out of 5 patients with MCTD. This assay appears to be applicable to the detection and quantification of circulating nRNP ICs in patients with MCTD.
我们开发了一种用于检测补体（C）固定核核糖核蛋白（nRNP）：抗nRNP免疫复合物（nRNP ICs）的固相放射免疫分析方法。该分析基于补体固定的nRNP ICs与固定化的F(ab')2抗C3强烈结合的能力。通过将与抗C3结合的补体固定的nRNP ICs与125I标记的抗nRNP特异性IgG孵育来定量结合程度。抗C3与补体固定的nRNP ICs之间的相互作用迅速，呈时间和浓度依赖性，并且在抗原抗体比例为8:1（每毫升相当于9.8 - 5000 ng人聚集IgG）的广泛nRNP IC浓度范围内敏感。我们发现该分析还能检测到Sm:抗Sm免疫复合物中的免疫反应性U1-RNP抗原，但检测不到SSA:抗SSA免疫复合物。该分析初步应用于从混合性结缔组织病（MCTD）患者获得的血清样本，在5例MCTD患者中有3例发现nRNP免疫复合物浓度升高。该分析似乎适用于检测和定量MCTD患者循环中的nRNP ICs。
