Monoclonal antibody variable region sequencing

The SARS-CoV-2 pandemic has demonstrated the need for increasing the diversity of ways to produce monoclonal antibody-based diagnostics and therapeutics against emerging viruses. This study was performed to highlight the utility of the baculovirus expression vector system (BEVS) in this context. A BEVS was used to produce SARS-CoV-2 full-length spike (S), S1 domain (S1), receptor binding domain (RBD) and nucleocapsid (NP) proteins which were then used to hyperimmunize Balb/c mice. Hybridoma technology was used to produce monoclonal antibodies (mAbs) which were then evaluated for their ability to neutralize SARS-CoV-2 variants in vitro. Eight anti-SS mAbs were found to neutralize SARS-CoV-2 Wuhan and Delta strains. These eight mAbs were further characterized by epitope mapping and variable region gene sequencing. The BEVS-produced antigens and the mAbs produced using these antigens were successfully used to develop diagnostics and therapeutics against SARS-CoV-2 variants. This study form a basis for further investigation into the BEVS and its potential for implementation in the production of mAbs for therapeutic and diagnostic uses.