Neutralizing antibody (NAb) is a family of antibodies with special functions, which afford a degree of protection against infection and/or reduce the risk of clinically severe infection. Receptor binding domain (RBD) in the spike protein of SARS-CoV-2, a portion of the S1 subunit, can stimulate the immune system to produce NAb after infection and vaccination. The detection of NAb against SARS-CoV-2 is a simple and direct approach for evaluating a vaccine’s effectiveness. In this study, a direct, rapid, and point-of-care bicolor lateral flow immunoassay (LFIA) was developed for NAb against SARS-CoV-2 detection without sample pretreatment, and which was based on the principle of NAb-mediated blockage of the interaction between RBD and angiotensin-converting enzyme 2. In the bicolor LFIA, red and blue latex microspheres (LMs) were used to locate the test and control lines, leading to avoidance of erroneous interpretations of one-colored line results. Under the optimal conditions, NAb against SARS-CoV-2 detection carried out using the bicolor LFIA could be completed within 9 min, and the visible limit of detection was about 48 ng/mL. Thirteen serum samples were analyzed, and the results showed that the NAb levels in three positive serum samples were equal to, or higher than, 736 ng/mL. The LM-based bicolor LFIA allows one-step, rapid, convenient, inexpensive, and user-friendly determination of NAb against SARS-CoV-2 in serum.
【저자키워드】 neutralizing antibody, SARS-CoV-2, Receptor binding domain, latex microspheres, lateral flow immunoassay, 【초록키워드】 Severe infection, vaccination, antibody, Infection, risk, immune system, angiotensin-converting enzyme 2, point-of-care, SARS-CoV-2 detection, serum, RBD, Interpretation, limit of detection, Effectiveness, LFIA, microsphere, Interaction, avoidance, functions, binding domain, positive, serum sample, approach, the S1 subunit, analyzed, carried, clinically, were used, the spike protein, reduce, conditions, stimulate, 【제목키워드】 detection, Qualitative, Latex,