The sVNT kit detects and measures circulating neutralizing antibodies against the SARS-CoV-2 virus. Neutralizing antibodies generated by the immune system after COVID-19 infection or vaccination function by blocking the interaction between the receptor binding domain (RBD) of the SARS-CoV-2 spike glycoprotein and the ACE2 human cell surface receptor. Because of the crucial role of neutralizing antibodies, many vaccine companies and drug developers focus on the analysis of these antibodies. For example, vaccine developers frequently report the neutralizing antibody response induced by their vaccines. Additionally, drug development companies are currently developing drugs based on neutralizing antibodies for the treatment of COVID-19 patients. The sVNT kit detects and measures neutralizing antibodies generated in response to COVID-19 vaccination. The kit also helps determine the efficacy of potential drugs at blocking the RBD-ACE2 interaction, regardless of whether these drugs are antibodies or small molecules. The kit further supports COVID-19 investigations of seroprevalence, assessment of herd immunity, and longevity of protective immunogenic response. The sVNT test is species-independent and can be used for studying the SARS-CoV-2 infection in animals such as rats, mice, ferrets, and rabbits. The kit is a faster, easier, and higher throughput alternative to a live virus assay for detecting neutralizing antibodies.
The sVNT test can be used for both qualitative and semi-quantitative detection of SARS-CoV-2 neutralizing antibodies. In the qualitative mode, the test signals the presence or absence of neutralizing antibodies in a sample. In the semi-quantitative mode, the test measures the relative amount of neutralizing antibodies against a calibrator using a standard curve (Figure 1a). The results are then displayed as High/Medium/Low neutralization (Figure 1b), or as Units/mL or titer depending on the user’s preference.