The pathogenic agent, namely SARS-CoV-2, is a kind of positive-sense RNA virus, consisting of spike (S) glycoprotein, membrane protein, envelope glycoprotein, lipid bilayer and inner structures . It belongs to the betacoronavirus genus whose family members include Middle East respiratory syndrome coronavirus (MERS-CoV) and SARS-associated coronavirus (SARS-CoV). Similar to the two family members, SARS-CoV-2 infects host cells through S protein which can interact with the angiotensin-converting enzyme 2 (ACE2) entry receptor on host membranes with high affinity . As a consequence, the S protein becomes the main target of neutralizing antibodies. S1 and S2 subunits are two functional components of the S protein, of which the former (S1) is further divided into receptor-binding domain (RBD) necessary for ACE2 binding, N-terminal domain (NTD) and other domains . So far, plenty of mAbs recognizing RBD have been discovered such as REGN10933 , S2M11 . Compared with RBD-specific mAbs, a small number of antibodies targeted to NTD have been developed. Nevertheless, it is reported that some NTD-targeting mAbs are capable of neutralizing SARS-CoV-2 infection in vitro with high potency . For instance, McCallum et al. described 41 NTD-specific human mAbs, among which S2X333 neutralized SARS-CoV-2 with an IC50 of 2 ng/mL, on par with the first-rate RBD mAbs S2E12 and S2M11 . Therefore, NTD may be another promising therapeutic target site.