Institute of Water Chemistry, Chair of Analytical Chemistry and Water Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85748, Garching, Germany.
Institute of Virology, Technical University of Munich/Helmholtz Zentrum München, Trogerstr. 30, 81675, Munich, Germany.
Anal Bioanal Chem. 2023 Jan;415(3):391-404. doi: 10.1007/s00216-022-04416-6. Epub 2022 Nov 8.
The SARS-CoV-2 pandemic has shown the importance of rapid and comprehensive diagnostic tools. While there are numerous rapid antigen tests available, rapid serological assays for the detection of neutralizing antibodies are and will be needed to determine not only the amount of antibodies formed after infection or vaccination but also their neutralizing potential, preventing the cell entry of SARS-CoV-2. Current active-virus neutralization assays require biosafety level 3 facilities, while virus-free surrogate assays are more versatile in applications, but still take typically several hours until results are available. To overcome these disadvantages, we developed a competitive chemiluminescence immunoassay that enables the detection of neutralizing SARS-CoV-2 antibodies within 7 min. The neutralizing antibodies bind to the viral receptor binding domain (RBD) and inhibit the binding to the human angiotensin-converting enzyme 2 (ACE2) receptor. This competitive binding inhibition test was characterized with a set of 80 samples, which could all be classified correctly. The assay results favorably compare to those obtained with a more time-intensive ELISA-based neutralization test and a commercial surrogate neutralization assay. Our test could further be used to detect individuals with a high total IgG antibody titer, but only a low neutralizing titer, as well as for monitoring neutralizing antibodies after vaccinations. This effective performance in SARS-CoV-2 seromonitoring delineates the potential for the test to be adapted to other diseases in the future.
SARS-CoV-2 大流行表明了快速全面的诊断工具的重要性。虽然有许多快速抗原检测方法，但需要快速血清学检测方法来检测中和抗体，以确定感染或接种疫苗后形成的抗体数量及其中和潜力，防止 SARS-CoV-2 进入细胞。目前的活病毒中和测定需要生物安全 3 级设施，而无病毒替代测定在应用中更具多功能性，但仍需要几个小时才能得到结果。为了克服这些缺点，我们开发了一种竞争性化学发光免疫测定法，能够在 7 分钟内检测到中和 SARS-CoV-2 的抗体。中和抗体与病毒的受体结合域 (RBD) 结合，并抑制与人类血管紧张素转换酶 2 (ACE2) 受体的结合。该竞争性结合抑制试验用 80 个样本进行了特征描述，这些样本都可以正确分类。该测定结果与更耗时的基于 ELISA 的中和测定和商业替代中和测定的结果相比具有优势。我们的测试可以进一步用于检测具有高总 IgG 抗体滴度但中和滴度低的个体，以及监测接种后的中和抗体。该测试在 SARS-CoV-2 血清监测中的有效性能表明，该测试将来有可能适应其他疾病。
