Filchtinski Daniel, Kayser José, Ettner Virginie, Holz Sanja, Kristensen Bjarne, Schulte-Pelkum Johannes, Wilhelm Isabel, Fiedler Raimund
Thermo Fisher Scientific, Freiburg, Germany.
Thermo Fisher Scientific, Freiburg, Germany.
J Immunol Methods. 2025 Aug;542:113885. doi: 10.1016/j.jim.2025.113885. Epub 2025 May 28.
In clinics, diabetes is determined by blood glucose levels or by glycosylated hemoglobin (HbA1c). However, to distinguish between Type 1 and Type 2 diabetes (T1D and T2D) for adequate treatment, patients are tested for the presence of Type 1 diabetes-relevant autoantibodies in the second tier. Anti-GAD65 autoantibody is one of the main markers for T1D in both pediatric and adult T1D patients. If the anti-GAD65 autoantibody is detectable, the patients have type 1 diabetes and need to be treated with insulin. In the clinical routine diagnostics of type 1 diabetes, GAD65-serology is performed using a special assay architecture known as bridging ELISA. Adapting these assays onto automated ELISA systems has shown to be a constant challenge, so they can be hardly applied for high throughput testing in a routine clinical laboratory.
We developed the first fully automated, high-throughput GAD65 autoantibody fluorescence enzyme immunoassay based on the bridging immunoassay format on Phadia instrument platform, termed EliA GAD65 and compared its performance with the bridging ELISA from RSR™ (GADAb ELISA) and the fully automated MAGLUMI® GAD65 chemiluminescence assay (CLIA) from Snibe Diagnostics.
When tested for clinical performance, ROC Analysis of EliA GAD65 showed an Area under the curve (AUC) of 0.906 (95 % CI 0.864 to 0.949) compared to the AUC of 0.923 (95 % CI 0.884to 0.963) of GADAb ELISA with no significant difference between the two assays (p = 0.384). When adjusted to a specificity of 96 %, EliA GAD65 showed a sensitivity of 76 % (CI 95 % 66.4 % to 84.0 %) compared to a sensitivity of 74 % (95 % CI 64.6 % to 81.6 %) of GADAb ELISA. When the fully automated MAGLUMI® GAD65 CLIA was compared to GADAb ELISA, it showed a total agreement of 92.9 % (95 % CI 86.6 % to 96.4 %) with less positive samples detected in contrast to the total agreement of 100 % (95 % CI 96.7 % to 100 %) of EliA GAD65 to GADAb ELISA.
Fully automated EliA GAD65 assay displays similar clinical characteristics as the well-established bridging GADAb ELISA and a higher agreement with the GADAb ELISA than the automated MAGLUMI® GAD65 CLIA.
在临床中，糖尿病通过血糖水平或糖化血红蛋白（HbA1c）来判定。然而，为了区分1型糖尿病和2型糖尿病（T1D和T2D）以便进行适当治疗，患者会在二级检测中检测是否存在与1型糖尿病相关的自身抗体。抗谷氨酸脱羧酶65（GAD65）自身抗体是儿童和成人T1D患者中T1D的主要标志物之一。如果可检测到抗GAD65自身抗体，则患者患有1型糖尿病，需要接受胰岛素治疗。在1型糖尿病的临床常规诊断中，GAD65血清学检测采用一种称为桥接ELISA的特殊检测架构。将这些检测方法应用于自动化ELISA系统一直是一项挑战，因此它们很难用于常规临床实验室的高通量检测。
我们基于Phadia仪器平台上的桥接免疫分析形式开发了首个全自动、高通量GAD65自身抗体荧光酶免疫分析方法，称为EliA GAD65，并将其性能与RSR™的桥接ELISA（GADAb ELISA）以及Snibe Diagnostics的全自动MAGLUMI® GAD65化学发光分析（CLIA）进行比较。
在进行临床性能测试时，EliA GAD65的ROC分析显示曲线下面积（AUC）为0.906（95%CI 0.864至0.949），而GADAb ELISA的AUC为0.923（95%CI 0.884至0.963），两种检测方法之间无显著差异（p = 0.384）。当调整到96%的特异性时，EliA GAD65的灵敏度为76%（95%CI 66.4%至84.0%），而GADAb ELISA的灵敏度为74%（95%CI 64.6%至81.6%）。当将全自动MAGLUMI® GAD65 CLIA与GADAb ELISA进行比较时，其总一致性为92.9%（95%CI 86.6%至96.4%），检测到的阳性样本较少，而EliA GAD65与GADAb ELISA的总一致性为100%（95%CI 96.7%至100%）。
全自动EliA GAD65检测方法显示出与成熟的桥接GADAb ELISA相似的临床特征，并且与GADAb ELISA的一致性高于自动化MAGLUMI® GAD65 CLIA。
