Defenses against SARS-CoV-2 variants
Our key defense against the COVID-19 pandemic is neutralizing antibodies against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus elicited by natural infection or vaccination. Recent emerging viral variants have raised concern because of their potential to escape antibody neutralization. Wang et al. identified four antibodies from early-outbreak convalescent donors that are potent against 23 variants, including variants of concern, and characterized their binding to the spike protein of SARS-CoV-2. Yuan et al. examined the impact of emerging mutations in the receptor-binding domain of the spike protein on binding to the host receptor ACE2 and to a range of antibodies. These studies may be helpful for developing more broadly effective vaccines and therapeutic antibodies.
Our study demonstrates that convalescent subjects previously infected with ancestral variant SARS-CoV-2 produce antibodies that cross-neutralize emerging VOCs with high potency. Structural and functional analyses reveal that antibody breadth is mediated by targeting a site of vulnerability at the RBD tip offset from major mutational hotspots in VOCs. Selective boosting of immune responses targeting specific RBD epitopes, such as the sites defined by these antibodies, may induce breadth against current and future VOCs.