Neutralization of wild-type and 1A9 escape SARS-CoV virus by mAb 1A9 and mAb 1G10.

<p>Wild-type human SARS-CoV HKU39849 strain (A and C) and escape mutant SARS-CoV virus generated in the presence mAb 1A9 (B and D) were used at 1000 TCID₅₀ to infect Vero E6 cells in the presence of two mAbs, namely mAb 1A9 (A and B) and mAb 1G10 (C and D). MAb 1A9 was used at concentrations 0, 0.25, 0.5, 1.0 and 2.0 mg/ml while mAb 1G10 was used at concentrations 0, 0.125, 0.25, 0.5 and 1.0 mg/ml. Percentage cytopathic effects (% CPE) of the infected cells was observed. MAb 1G10, a SARS-CoV-neutralizing, anti-S2 mAb that binds to S2 at residues 1151–1192, was used as the control mAb.