Department of Immunopathology, SA Pathology, Adelaide, SA, Australia; Department of Allergy and Clinical Immunology, Flinders Medical Centre, Bedford Park, SA, Australia; Flinders University, Bedford Park, SA, Australia.
Department of Immunopathology, SA Pathology, Adelaide, SA, Australia.
Pathology. 2022 Dec;54(7):910-916. doi: 10.1016/j.pathol.2022.07.010. Epub 2022 Sep 14.
Lens-epithelial derived growth factor (LEDGF/DFS70) autoantibodies result in the commonly observed dense fine speckled (DFS) pattern by anti-nuclear antibody (ANA) assay. However, there is no consensus approach for confirmation of this autoantibody specificity. To evaluate current approaches, we examined inter-assay agreement between six anti-LEDGF/DFS70 assays. A total of 395 consecutive sera samples from routine ANA diagnostics were obtained, tested by routine ANA, anti-ENA line immunoblot assay (LIA) and anti-dsDNA assay and with six anti-DFS/LEDGF assays: the EuroLine-LIA (Euro-LIA), Medical and Biological Laboratories ELISA (MBL-ELISA), Phadia-EliA (EliA), QUANTA Flash CLIA, EuroImmun ELISA (Euro-ELISA) and Immco-Diagnostics HEp-2 ELITE/DFS-Knockout (HEp-2KO). Of 395 sera, 108 tested positive by at least one assay. Despite general good concordance between all assays across the cohort (Gwet's AC1=0.89), within the target DFS-ANA pattern group inter-assay agreement was poor (AC1=0.59). Euro-LIA, CLIA and MBL-ELISA assays were most concordant, but CLIA and Euro-LIA were also most likely to identify discordant positive results. EliA and Euro-ELISA had poorer agreement, which could be attributable to ill-matched cut-offs between assays. HEp-2KO was frequently discordant with all other assays tested. Euro-LIA, CLIA and MBL-ELISA were most concordant at manufacturer's specifications and are suited for use in clinical laboratories. Modified assay thresholds are required to ensure comparative results for Euro-ELISA and EliA. HEp-2KO assay is frequently discordant with all other assays, making it less suited for routine diagnostics. The study highlights the importance of considering inter-assay variability when developing a diagnostic strategy for anti-LEDGF/DFS70 autoantibodies in clinical laboratories.
晶状体上皮衍生生长因子 (LEDGF/DFS70) 自身抗体通过抗核抗体 (ANA) 检测导致常见的弥漫性细颗粒状 (DFS) 模式。然而，对于这种自身抗体特异性的确认，目前还没有共识的方法。为了评估当前的方法，我们检查了六种抗 LEDGF/DFS70 检测方法之间的实验内一致性。共获得 395 例来自常规 ANA 诊断的连续血清样本，通过常规 ANA、抗 ENA 线免疫印迹检测 (LIA) 和抗 dsDNA 检测以及六种抗 DFS/LEDGF 检测进行检测：EuroLine-LIA (Euro-LIA)、Medical and Biological Laboratories ELISA (MBL-ELISA)、Phadia-EliA (EliA)、QUANTA Flash CLIA、EuroImmun ELISA (Euro-ELISA) 和 Immco-Diagnostics HEp-2 ELITE/DFS-Knockout (HEp-2KO)。在 395 例血清中，有 108 例至少有一种检测方法呈阳性。尽管所有检测方法在整个队列中的一致性都很好 (Gwet 的 AC1=0.89)，但在目标 DFS-ANA 模式组内，实验内一致性较差 (AC1=0.59)。Euro-LIA、CLIA 和 MBL-ELISA 检测方法最一致，但 CLIA 和 Euro-LIA 也最有可能识别不一致的阳性结果。EliA 和 Euro-ELISA 的一致性较差，这可能归因于检测之间不匹配的截止值。HEp-2KO 与所有其他检测方法经常不一致。在制造商的规格下，Euro-LIA、CLIA 和 MBL-ELISA 最一致，适合在临床实验室使用。需要修改检测阈值，以确保 Euro-ELISA 和 EliA 的比较结果。HEp-2KO 检测与所有其他检测方法经常不一致，因此不太适合常规诊断。该研究强调了在临床实验室开发抗 LEDGF/DFS70 自身抗体诊断策略时考虑实验内变异性的重要性。
