Figure 1.

Anti-SARS-CoV-2 neutralizing mAbs, casirivimab and imdevimab, have the potential to cause ADE of infection. (A,B) Clone 35 cells (2 × 10⁴/well in a 96-well flat plate) were cultured with SARS-CoV-2 (original strain, 4 × 10³ copies/μL) in the presence (N = 3) or absence (N = 3–6, control culture) of serially-diluted Cas, Imd, or isotype control Abs as indicated. Three days later, the amount of virus in culture SNs was measured by qPCR. The increase of virus progeny in SNs is expressed as the fold increase compared with the amount of viruses cultured in the absence of Abs. (C) Clone 35 cells were cultured with SARS-CoV-2 in the presence or absence of a constant dose of the indicated Abs (final 1 ng/mL each) as in (A). Each symbol represents individual experiments. (D,E) Clone 35 cells were cultured as in (A), but with a low dose of SARS-CoV-2 (40 copies/μL). Each symbol represents individual wells (N = 20 per group).