Hirschberg Stefan, Bauer Hannes, Kamhieh-Milz Julian, Ringel Frauke, Harms Christoph, Eddin Omar Kamal, Pruß Axel, Hanack Katja, Schulze-Forster Kai
Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Transfusion Medicine, 10117 Berlin, Germany.
CellTrend GmbH, 14943 Luckenwalde, Germany.
Antibodies (Basel). 2022 Dec 12;11(4):76. doi: 10.3390/antib11040076.
A key in controlling the SARS-CoV-2 pandemic is the assessment of the immune status of the population. We explored the utility of SARS-CoV-2 virus-like particles (VLPs) as antigens to detect specific humoral immune reactions in an enzyme-linked immunosorbent assay (ELISA). For this purpose, SARS-CoV-2 VLPs were produced from an engineered cell line and characterized by Western blot, ELISA, and nanoparticle tracking analysis. Subsequently, we collected 42 serum samples from before the pandemic (2014), 89 samples from healthy subjects, and 38 samples from vaccinated subjects. Seventeen samples were collected less than three weeks after infection, and forty-four samples more than three weeks after infection. All serum samples were characterized for their reactivity with VLPs and the SARS-CoV-2 N- and S-protein. Finally, we compared the performance of the VLP-based ELISA with a certified in vitro diagnostic device (IVD). In the applied set of samples, we determined a sensitivity of 95.5% and a specificity of 100% for the certified IVD. There were seven samples with an uncertain outcome. Our VLP-ELISA demonstrated a superior performance, with a sensitivity of 97.5%, a specificity of 100%, and only three uncertain outcomes. This result warrants further research to develop a certified IVD based on SARS-CoV-2 VLPs as an antigen.
控制新型冠状病毒肺炎大流行的一个关键是评估人群的免疫状态。我们探索了使用新型冠状病毒病毒样颗粒（VLP）作为抗原，在酶联免疫吸附测定（ELISA）中检测特异性体液免疫反应的效用。为此，从一个工程细胞系生产新型冠状病毒VLP，并通过蛋白质印迹法、ELISA和纳米颗粒跟踪分析进行表征。随后，我们收集了大流行前（2014年）的42份血清样本、89份健康受试者的样本和38份接种疫苗受试者的样本。17份样本在感染后不到三周收集，44份样本在感染后三周以上收集。所有血清样本均针对其与VLP以及新型冠状病毒N蛋白和S蛋白的反应性进行表征。最后，我们将基于VLP的ELISA性能与一种经认证的体外诊断设备（IVD）进行了比较。在所应用的样本集中，我们确定经认证的IVD的灵敏度为95.5%，特异性为100%。有7份样本结果不确定。我们的VLP-ELISA表现出更优的性能，灵敏度为97.5%，特异性为100%，只有3份结果不确定。这一结果值得进一步研究，以开发一种基于新型冠状病毒VLP作为抗原的经认证的IVD。
