(A) Huh7.5 cells were pre-incubated with neutralizing antibody to ACE2 and SARS-CoV-2 pseudovirus was pre-incubated with patient isolated mAb COVA1-18, COVA1-21 and COVA2-15 (10 µg/mL) or UF heparin (250 IU/mL) for 30 min at 37°C. SARS-CoV-2 pseudovirus alone or with blocks was added to the cells for 4h at 4°C and binding was determined by ELISA. Data information: Data show the mean values and error bars are the SEM. Statistical analysis was performed using ordinary one-way ANOVA with Tukey multiple-comparison test. *P≤0.05, **P≤0.01, ***P≤0.001(n=3) 