Evaluating Antibody Efficacy Against SARS-CoV-2 in Humanized Mice

All work with SARS-CoV-2 was performed in a BSL3 facility. Six- to eight-week-old female BALB/c mice (Jackson Laboratory) were administered an adenovirus expressing human ACE2 (AdV-hACE2) via the intranasal route at 2.5 × 10⁸ PFU per mouse in a final volume of 50 μl. Five days later, each respective antibody was administered via the intraperitoneal route at 10 mg/kg in a 100-μl volume. Two hours later, mice were infected with 10⁵ PFU of SARS-CoV-2 intranasally. Mice were humanely sacrificed on day 3 and day 5 to assess the viral titers in the lungs. Lungs were homogenized using a BeadBlaster 24 (Benchmark) homogenizer. Each lung homogenate was tested in a classical plaque assay as described previously (44 (link), 47 (link)).