Neuroinflammation and Neuroimmunology Lab, Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, Brazil.
School of Medicine, Graduate Program in Pediatrics and Child Health, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, Brazil.
Front Immunol. 2021 May 7;12:642272. doi: 10.3389/fimmu.2021.642272. eCollection 2021.
Human antibodies against Myelin Oligodendrocyte Glycoprotein (MOG) from immunoglobulin-G subclasses (MOG-IgG) have been recently associated with a new subgroup of neurological autoimmune diseases with distinct clinical characteristics from multiple sclerosis and neuromyelitis optica spectrum disorders. The use of MOG-IgG as a biomarker is an essential tool to assist in the diagnosis and clinical prognosis. The cell-based assay (CBA) is a methodology that expresses high levels of natively folded human MOG protein in the cell membrane being the methodology most used for clinical MOG-IgG diagnosis. However, there is still no consensus about the best approach to perform CBA to improve the results. The CBA using flow cytometry (CBA-FC) is an automated technique with objective quantification, reducing the subject of human bias that occurred at CBA using immunofluorescence (CBA-IF). In this study, we compared the performance of CBA-IF and CBA-FC as an acquisition tool analysis. The sera of 104 patients diagnosed with inflammatory Central Nervous System diseases were tested in both CBA-IF and CBA-FC. We used the dilution of 1:128 for CBA-IF and three different dilutions (1:20, 1:100, and 1:640) for CBA-FC. The CBA-FC and CBA-IF results had 88.5% agreement between assays and the CBA-IF titers by endpoint-dilution correlated with the CBA-FC titers. The highest serum dilution resulted in an increased CBA-FC specificity, but there was a reduction in the CBA-FC sensitivity. Our study showed that CBA-FC can be used in clinical practice as a diagnostic technique for MOG-IgG. In addition, in some specific cases, the combination of both techniques could be used as a tool to discriminate unspecific binding and overcome single assay limitations.
人类抗髓鞘少突胶质细胞糖蛋白（MOG）抗体来自免疫球蛋白-G 亚类（MOG-IgG），最近与一组具有独特临床特征的新的神经自身免疫性疾病相关，与多发性硬化症和视神经脊髓炎谱系障碍不同。MOG-IgG 的使用作为一种生物标志物是辅助诊断和临床预后的重要工具。基于细胞的测定法（CBA）是一种在细胞膜中表达高水平天然折叠人 MOG 蛋白的方法，是用于临床 MOG-IgG 诊断的最常用方法。然而，对于提高结果，仍然没有关于执行 CBA 的最佳方法的共识。使用流式细胞术的 CBA（CBA-FC）是一种自动化技术，具有客观的定量分析，减少了在使用免疫荧光法的 CBA 中发生的人为偏见。在这项研究中，我们比较了 CBA-IF 和 CBA-FC 作为采集工具分析的性能。在两种 CBA-IF 和 CBA-FC 中检测了 104 名诊断为炎症性中枢神经系统疾病的患者的血清。我们使用 1:128 稀释度进行 CBA-IF，并用三种不同的稀释度（1:20、1:100 和 1:640）进行 CBA-FC。CBA-FC 和 CBA-IF 之间的检测结果有 88.5%的一致性，终点稀释的 CBA-IF 滴度与 CBA-FC 滴度相关。最高的血清稀释度导致 CBA-FC 特异性增加，但 CBA-FC 敏感性降低。我们的研究表明，CBA-FC 可以在临床上用作 MOG-IgG 的诊断技术。此外，在某些特定情况下，这两种技术的结合可用于作为区分非特异性结合和克服单一检测局限性的工具。
