Fig. 2.

Neutralizing activity of mAbs (A: N-176-15 and B: S-9-11) at different doses was determined by syncytia inhibition assay. The method is the same as that described in Fig. 1. ‘+’: no mAb or antiserum. ‘No ACE2’: HEK293T cells without ACE2 plasmid transfection. ‘U’: An anti-mouse CD4 mAb selected as an unrelated control. ‘S’: mAb S-9-11, ‘N’: mAb N-176-15, the volume of mAb ascites added into each well (with medium of 1 ml) was also marked.