Christensen Troels D, Maag Emil, Madsen Kasper, Lindgaard Sidsel Christy, Nielsen Dorte L, Johansen Julia S
Department of Oncology, Copenhagen University Hospital - Herlev and Gentofte, Borgmester Ib Juuls Vej 1, 2730, Herlev, Denmark.
BioXpedia, Aarhus, Denmark.
Clin Proteomics. 2022 Nov 15;19(1):39. doi: 10.1186/s12014-022-09380-y.
Proximity extension assay (PEA) is a novel antibody-based proteomic technology. Sparse data have been published concerning the matrix effect of serum vs. ethylenediamine tetraacetic acid (EDTA) plasma and the reproducibility of results obtained using PEA technology.
We analyzed samples with the PEA-based 92-plex Olink® immuno-oncology (I-O) assay. To estimate the matrix effect, we analyzed paired serum and EDTA plasma samples from 12 patients with biliary tract cancer. To evaluate the reproducibility, we used data from 7 studies, where 6-8 serum samples from patients with pancreatic cancer were used as bridging samples on 3 versions of the panel over a 2.5-years period.
For the study of serum vs. plasma, 80 proteins were evaluable. The mean serum to EDTA plasma ratio ranged from 0.41-3.01. For 36 proteins, the serum and plasma values were not comparable due to high variability of the ratio, poor correlation, or possible concentration effect. For the bridging samples, the mean intra-study inter-assay coefficient of variation (CV) ranged from 11.3% to 26.1%. The mean inter-study CV was 42.0% before normalization and 26.2% after normalization. Inter-study results were well correlated (r ≥ 0.93), especially for studies using the same version of the panel (r ≥ 0.99).
For 44 of 92 proteins included in the Olink® I-O panel, the variation between results obtained using serum and EDTA plasma was constant and results were well correlated. Furthermore, samples could be stored for several years and used on different versions of the same PEA panel without it effecting results.
邻近延伸分析（PEA）是一种基于抗体的新型蛋白质组学技术。关于血清与乙二胺四乙酸（EDTA）血浆的基质效应以及使用PEA技术获得结果的可重复性，已发表的数据较少。
我们使用基于PEA的92重Olink®免疫肿瘤学（I-O）分析对样本进行了分析。为了评估基质效应，我们分析了12例胆管癌患者的配对血清和EDTA血浆样本。为了评估可重复性，我们使用了7项研究的数据，在2.5年的时间里，将6-8例胰腺癌患者的血清样本作为桥接样本用于3个版本的检测板。
对于血清与血浆的研究，80种蛋白质可进行评估。血清与EDTA血浆的平均比值在0.41至3.01之间。对于36种蛋白质，由于比值的高变异性、低相关性或可能的浓度效应，血清和血浆值不具有可比性。对于桥接样本，研究内平均批间变异系数（CV）在11.3%至26.1%之间。研究间平均CV在标准化前为42.0%，标准化后为26.2%。研究间结果相关性良好（r≥0.93），特别是对于使用相同版本检测板的研究（r≥0.99）。
在Olink® I-O检测板所包含的92种蛋白质中，有44种蛋白质使用血清和EDTA血浆获得的结果之间的差异是恒定的，且结果相关性良好。此外，样本可以保存数年，并用于同一PEA检测板的不同版本，而不会影响结果。
