Mishra K P, Singh Mrinalini, Saraswat Deepika, Singh Somnath
Immunomodulation Laboratory, Defence Institute of Physiology and Allied Sciences, Delhi, India.
Viral Immunol. 2023 Oct;36(8):495-502. doi: 10.1089/vim.2023.0058. Epub 2023 Aug 29.
Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) stimulates the plasma B cells to secrete specific antibodies against the viral antigen. However, not all antibodies can prevent the virus from entering the cells. The subpopulation of antibodies which blocks the entry of the virus into host cells is termed neutralizing antibodies (NAbs). The gold standard test for the detection of NAbs is the viral plaque reduction and neutralization test; however, various other methods can also be utilized to detect NAbs. In this study, we have developed an Enzyme Linked Immunosobent Assay (ELISA)-based protocol for rapid detection of SARS CoV-2 NAb by inhibiting the binding of the spike protein receptor-binding domain to angiotensin converting enzyme 2 and compared it with cPASS neutralizing antibody kit, which was approved by the Food and Drug Administration (FDA). The results obtained suggest that the in-house ELISA developed for the detection of NAbs against SARS-CoV-2 is rapid and reliable. Compared to FDA-approved GenScript's cPass assay, the specificity and the sensitivity of the in-house-developed ELISA kit were 100% (95% confidence intervals of 69.15-100.00) and 96% (95% confidence intervals of 86.29-99.51), respectively. Thus, the ELISA protocol developed to test the neutralizing activities of antibodies is rapid, which requires a BSL-2 infrastructure facility and can be easily performed. It has very high potential applications in the rapid screening of NAb against SARS-CoV-2.
严重急性呼吸综合征冠状病毒2（SARS-CoV-2）感染刺激血浆B细胞分泌针对病毒抗原的特异性抗体。然而，并非所有抗体都能阻止病毒进入细胞。能够阻断病毒进入宿主细胞的抗体亚群被称为中和抗体（NAbs）。检测中和抗体的金标准试验是病毒蚀斑减少中和试验；然而，也可以使用各种其他方法来检测中和抗体。在本研究中，我们开发了一种基于酶联免疫吸附测定（ELISA）的方案，通过抑制刺突蛋白受体结合结构域与血管紧张素转换酶2的结合来快速检测SARS-CoV-2中和抗体，并将其与美国食品药品监督管理局（FDA）批准的cPASS中和抗体试剂盒进行比较。所得结果表明，所开发的用于检测针对SARS-CoV-2中和抗体的内部ELISA方法快速且可靠。与FDA批准的金斯瑞cPass检测法相比，内部开发的ELISA试剂盒的特异性和灵敏度分别为100%（95%置信区间为69.15 - 100.00）和96%（95%置信区间为86.29 - 99.51）。因此，所开发的用于检测抗体中和活性的ELISA方案快速，需要二级生物安全水平（BSL-2）基础设施且易于操作。它在快速筛选针对SARS-CoV-2的中和抗体方面具有非常高的潜在应用价值。
