Wilkins Deidre, Aksyuk Anastasia A, Ruzin Alexey, Tuffy Kevin M, Green Tina, Greway Rebecca, Fikes Brittany, Bonhomme Cyrille J, Esser Mark T, Kelly Elizabeth J
Translational Medicine, Vaccines and Immune Therapies BioPharmaceuticals Medical AstraZeneca Gaithersburg MD USA.
PPD® Laboratories Vaccine Sciences Lab Richmond VA USA.
Clin Transl Immunology. 2022 Apr 26;11(4):e1385. doi: 10.1002/cti2.1385. eCollection 2022.
Robust, quantitative serology assays are required to accurately measure antibody levels following vaccination and natural infection. We present validation of a quantitative, multiplex, SARS-CoV-2, electrochemiluminescent (ECL) serology assay; show correlation with two established SARS-CoV-2 immunoassays; and present calibration results for two SARS-CoV-2 reference standards.
Precision, dilutional linearity, ruggedness, analytical sensitivity and specificity were evaluated. Clinical sensitivity and specificity were assessed using serum from prepandemic and SARS-CoV-2 polymerase chain reaction (PCR)-positive patient samples. Assay concordance to the established Roche Elecsys® Anti-SARS-CoV-2 immunoassay and a live-virus microneutralisation (MN) assay was evaluated.
Standard curves demonstrated the assay can quantify SARS-CoV-2 antibody levels over a broad range. Assay precision (10.2-15.1% variability), dilutional linearity (≤ 1.16-fold bias per 10-fold increase in dilution), ruggedness (0.89-1.18 overall fold difference), relative accuracy (107-118%) and robust selectivity (102-104%) were demonstrated. Analytical sensitivity was 7, 13 and 7 arbitrary units mL for SARS-CoV-2 spike (S), receptor-binding domain (RBD) and nucleocapsid (N) antigens, respectively. For all antigens, analytical specificity was > 90% and clinical specificity was 99.0%. Clinical sensitivities for S, RBD and N antigens were 100%, 98.8% and 84.9%, respectively. Comparison with the Elecsys® immunoassay showed ≥ 87.7% agreement and linear correlation (Pearson of 0.85, < 0.0001) relative to the MN assay. Conversion factors for the WHO International Standard and Meso Scale Discovery® Reference Standard are presented.
The multiplex SARS-CoV-2 ECL serology assay is suitable for efficient, reproducible measurement of antibodies to SARS-CoV-2 antigens in human sera, supporting its use in clinical trials and sero-epidemiology studies.
需要可靠的定量血清学检测方法来准确测量疫苗接种和自然感染后的抗体水平。我们展示了一种定量、多重、SARS-CoV-2电化学发光（ECL）血清学检测方法的验证；显示了与两种已建立的SARS-CoV-2免疫检测方法的相关性；并展示了两种SARS-CoV-2参考标准品的校准结果。
评估了精密度、稀释线性、耐用性、分析灵敏度和特异性。使用大流行前和SARS-CoV-2聚合酶链反应（PCR）阳性患者样本的血清评估临床灵敏度和特异性。评估了该检测方法与已建立的罗氏Elecsys®抗SARS-CoV-2免疫检测方法和活病毒微量中和（MN）检测方法的一致性。
标准曲线表明该检测方法能够在很宽的范围内定量SARS-CoV-2抗体水平。展示了检测精密度（变异率为10.2 - 15.1%）、稀释线性（每10倍稀释偏差≤1.16倍）、耐用性（总体倍数差异为0.89 - 1.18）、相对准确度（107 - 118%）和稳健选择性（102 - 104%）。SARS-CoV-2刺突蛋白（S）、受体结合域（RBD）和核衣壳（N）抗原的分析灵敏度分别为7、13和7任意单位/毫升。对于所有抗原，分析特异性>90%，临床特异性为99.0%。S、RBD和N抗原的临床灵敏度分别为100%、98.8%和84.9%。与Elecsys®免疫检测方法的比较显示一致性≥87.7%，相对于MN检测方法呈线性相关（Pearson相关系数为0.85，P<0.0001）。给出了世界卫生组织国际标准品和Meso Scale Discovery®参考标准品的换算因子。
多重SARS-CoV-2 ECL血清学检测方法适用于高效、可重复地测量人血清中针对SARS-CoV-2抗原的抗体，支持其在临床试验和血清流行病学研究中的应用。
