Precision Medicine, Oncology R&D, AstraZeneca, Cambridge, United Kingdom.
Research and Development Centre, Sysmex, Cambridge, United Kingdom.
J Immunol Methods. 2022 Jan;500:113181. doi: 10.1016/j.jim.2021.113181. Epub 2021 Nov 9.
Eosinophil-derived neurotoxin (EDN) is a surrogate biomarker of eosinophil activation and has considerable potential as a precision medicine biomarker in diseases where eosinophils may play a causative role. Clinical data for EDN have been generated using different quantitative immunoassays, but comparisons between these individual data sets are challenging as no internationally recognised EDN standards or orthogonal methods exist. In this study we aimed to compare commercial EDN assays from ALPCO, MBL, LSBio and CUSABIO for sample commutability. Firstly, we analytically validated the ALPCO enzyme linked immunosorbent assay (ELISA) and demonstrated appropriate analytical characteristics, including an intra/inter-assay precision coefficient-of-variation of between 1.9 and 6.8%. EDN purified from blood proved to be a good quality control material, whereas recombinant EDN, expressed in E.coli, did not react in the ALPCO immunoassay. Using healthy and asthma patient serum samples we confirmed that the ALPCO assay correlated well with the MBL assay, with a coefficient of determination (R) of 0.92. However, the results from LSBio and CUSABIO assays were not commutable to the other assays.
嗜酸性粒细胞衍生的神经毒素（EDN）是嗜酸性粒细胞活化的替代生物标志物，在嗜酸性粒细胞可能起致病作用的疾病中，具有作为精准医学生物标志物的巨大潜力。已经使用不同的定量免疫测定法生成了 EDN 的临床数据，但由于没有国际公认的 EDN 标准或正交方法，因此比较这些单独的数据组具有挑战性。在这项研究中，我们旨在比较来自 ALPCO、MBL、LSBio 和 CUSABIO 的商业 EDN 测定法在样品可互换性方面的差异。首先，我们对 ALPCO 酶联免疫吸附测定（ELISA）进行了分析验证，并证明了适当的分析特性，包括在 1.9%至 6.8%之间的内/间分析精密度变异系数。从血液中纯化的 EDN 被证明是一种质量控制良好的材料，而在大肠杆菌中表达的重组 EDN 则不会在 ALPCO 免疫测定中反应。使用健康和哮喘患者的血清样本，我们证实 ALPCO 测定法与 MBL 测定法相关性良好，决定系数（R）为 0.92。然而，LSBio 和 CUSABIO 测定法的结果与其他测定法不可互换。
