Molecular engineered low-cost highly effective RBD-based COVID vaccine Vaccine Coronavirus Disease COVID SARSCoV2 RBD biorxivpreprint MIT WestVirginiaU marshallu UnivOfKansas gatesfoundation ragoninstitute
Study: Molecular engineering of a cryptic epitope in Spike RBD improves manufacturability and neutralizing breadth against SARS-CoV-2 variants. Image Credit: Design_Cells / Shutterstock
About the study In the present study, researchers expanded their previous analysis by performing further molecular engineering analyses of the engineered SARS-CoV-2 RBD. RBD-J6 binding to ACE2 and several nAbs targeting different RBD epitopes was assessed. Next, the team evaluated polyclonal Ab raise in RBD-J bound to RBD-J6-vaccinated mice and binding of serological Abs obtained from SARS-CoV-2 Delta VOC-infected and coronavirus disease 2019 messenger ribonucleic acid vaccine-immunized convalescents to the initially and subsequently engineered RBDs was evaluated.
Results RBD-J6 showed binding with sera of Delta convalescent individuals and for all nAbs tested except the RBD core class IV epitope-targeting nAbs . The hydrophobic patch modification improved RBD secretion titers three-fold and enhanced stability; however, the modifications did now show significant differences in RBD immunogenicity or antigenicity.