Directed evolution of a stem-helix–targeting antibody enables MERS-CoV cross-neutralization through enhanced binding affinity
The isolation of a human monoclonal antibody from a SARS-CoV-2 convalescent donor that targets the conserved S2 stem helix region is reported, demonstrating the potential of in vitro affinity maturation to expand the neutralization breadth of stem-helix-targeting antibodies across divergent betacoronaviruses.