A human neutralizing antibody targets the receptor binding site of SARS-CoV-227 May, 2020
An outbreak of the coronavirus disease 2019 (COVID-19)1–3, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)4 spread globally. Countermeasures are needed to treat and prevent further dissemination of the virus. In this study, we report the isolation of 2 specific human monoclonal antibodies (MAbs) from a convalescent COVID-19 patient. CA1 and CB6 demonstrated potent SARS-CoV-2-specific neutralization activity in vitro against SARS-CoV-2. In addition, CB6 inhibited SARS-CoV-2 infection in rhesus monkeys at both prophylactic and treatment settings. Further structural studies revealed that CB6 recognizes an epitope that overlaps with angiotensin converting enzyme 2 (ACE2)-binding sites in SARS-CoV-2 receptor binding domain (RBD), thereby interfering with the virus/receptor interactions by both steric hindrance and direct interface-residue competition. Our results suggest CB6 deserves further clinical translation.