Trier Nicole Hartwig, Holm Bettina Eide, Heiden Julie, Slot Ole, Locht Henning, Jensen Bente, Lindegaard Hanne, Svendsen Anders, Nielsen Christoffer Tandrup, Jacobsen Søren, Theander Elke, Houen Gunnar
Department of Autoimmunology and Biomarkers, Statens Serum Institut, Artillerivej 5, 2300 Copenhagen S, Denmark.
Department of Autoimmunology and Biomarkers, Statens Serum Institut, Artillerivej 5, 2300 Copenhagen S, Denmark.
J Immunol Methods. 2018 Mar;454:6-14. doi: 10.1016/j.jim.2017.11.004. Epub 2017 Nov 8.
Rheumatoid arthritis (RA) is an autoimmune disease of unknown etiology. A characteristic feature of RA is the presence of anti-citrullinated protein antibodies (ACPA). Since ACPAs are highly specific for RA and are often present before the onset of RA symptoms, they have become valuable diagnostic and prognostic. As a result, several assays for detection of ACPAs exist, which vary in sensitivity and specificity. In this study, we analyzed the reactivity of RA sera to selected peptides by solid-phase immunoassays in order to develop an ACPA assay with improved sensitivity and specificity. ACPA levels were determined with respect to sensitivity and specificity in 332 serum samples using the newly developed peptide panel, which was compared to the commercial assays CCPlus (Eurodiagnostica) and CCP3.1 (Inova Diagnostics). A primary panel (peptides 814, 33062 and 33156) was identified, which obtained a sensitivity of 71%, while the complete peptide panel reacted with 79% of RA sera screened. Total specificities of 89% and 80% were obtained for the primary peptide panel and the complete peptide panel. Sensitivities for the commercial assays ranged between 71% and 76% and specificities between 88% and 90%. These findings indicate that the generated peptide panel is optimal for ACPA detection and able to compete with commercial available assays. Collectively, this study may contribute to characterize autoimmunity towards citrullinated proteins and to the development of new and improved diagnostic assays for detection of ACPA and determination of RA.
类风湿关节炎（RA）是一种病因不明的自身免疫性疾病。RA的一个特征是存在抗瓜氨酸化蛋白抗体（ACPA）。由于ACPA对RA具有高度特异性，且常在RA症状出现之前就已存在，因此它们具有重要的诊断和预后价值。结果，出现了几种检测ACPA的方法，这些方法在灵敏度和特异性上有所不同。在本研究中，我们通过固相免疫测定分析了RA血清对选定肽段的反应性，以开发一种灵敏度和特异性更高的ACPA检测方法。使用新开发的肽段组合，在332份血清样本中测定了ACPA水平的灵敏度和特异性，并将其与商业检测方法CCPlus（Eurodiagnostica）和CCP3.1（Inova Diagnostics）进行比较。确定了一个主要肽段组合（肽段814、33062和33156），其灵敏度为71%，而完整的肽段组合与79%的筛查RA血清发生反应。主要肽段组合和完整肽段组合的总特异性分别为89%和80%。商业检测方法的灵敏度在71%至76%之间，特异性在88%至90%之间。这些发现表明，所生成的肽段组合对于ACPA检测是最佳的，并且能够与市售检测方法竞争。总体而言，本研究可能有助于表征针对瓜氨酸化蛋白的自身免疫，并有助于开发用于检测ACPA和诊断RA的新的和改进的诊断方法。
