Globally, the COVID-19 pandemic has had extreme consequences for the healthcare system and calls for diagnostic tools to monitor and understand the transmission, pathogenesis and epidemiology, as well as to evaluate future vaccination strategies. Here we have developed novel flexible ELISA-based assays for specific detection of SARS-CoV-2 antibodies against the receptor-binding domain (RBD): An antigen sandwich-ELISA relevant for large population screening and three isotype-specific assays for in-depth diagnostics. Their performance was evaluated in a cohort of 350 convalescent participants with previous COVID-19 infection, ranging from asymptomatic to critical cases. We mapped the antibody responses to different areas on protein N and S and showed that the IgM, A and G antibody responses against RBD are significantly correlated to the disease severity. These assays-and the data generated from them-are highly relevant for diagnostics and prognostics and contribute to the understanding of long-term COVID-19 immunity.

中文翻译：

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SARS-CoV-2抗体反应决定了感染COVID-19的个体的疾病严重程度

在全球范围内，COVID-19大流行对医疗保健系统产生了严重后果，并呼吁使用诊断工具来监视和了解传播，发病机制和流行病学，并评估未来的疫苗接种策略。在这里，我们已经开发出了新的基于灵活ELISA的检测方法，用于特异性检测针对受体结合结构域（RBD）的SARS-CoV-2抗体：一种与大型人群筛查相关的抗原夹心ELISA，以及三种用于深入检测同种型的特异性检测诊断。在350名接受过COVID-19感染的恢复期参与者中评估了他们的表现，范围从无症状到严重。我们将抗体反应映射到蛋白质N和S的不同区域，结果显示IgM，针对RBD的A和G抗体反应与疾病严重程度显着相关。这些测定法以及由此产生的数据与诊断和预后高度相关，有助于理解长期COVID-19免疫力。