Fig. 3: Passive immunization with ShAb01 and ShAb02 protect mice from SARS-CoV-2 challenge.
From: Shark nanobodies with potent SARS-CoV-2 neutralizing activity and broad sarbecovirus reactivity
a Schematic of K18-hACE2 mice SARS-CoV-2 challenge study. Mice (n = 13/group, 7 female, 6 male; 15/group for the isotype control, 8 female, 7 male) received an intraperitoneal injection of ShAb01 (blue), or ShAb02 (green), or IgG1 isotype control mAb (black), one day prior to challenge with 1.25 × 104 PFU of SARS-CoV-2 virus (WA-1/2020). A cohort of mice (n = 5/group) were sacrificed 2 days post-challenge with the BAL fluid analyzed for viral load. The remaining mice (n = 8/group or 10 for the isotype control group) were assessed daily for weight and clinical symptoms. b Body weight measurements for K18-hACE2 mice. Percentage of initial weight is plotted. Isotype control mAb (black diamond), or ShAb01 (blue triangle) or ShAb02 (green circle). c Clinical score measurements of the K18-hACE2 study groups. All animals in the isotype control group were euthanized by study day 8. d Survival of K18-hACE2 mice for the 3 study groups. Key is shown in panel. Survival curves were compared individually to the isotype control using a Mantel-Cox log-rank test, and the significant P-value (P < 0.0001) is shown. n.s. indicates not significant differences. e SARS-CoV-2 viral loads in BAL were measured 2 days post-challenge in a subset of animals (n = 5/group) by plaque assay. Asterisks indicate significance compared to the antibody isotype control group by one-way ANOVA with Dunn’s multiple comparisons test, **P < 0.01. Source data are provided as a Source Data file. The mouse image was created with BioRender.com.
