Figure 2.
Fc effector functions enhance the therapeutic activity of a neutralizing antibody against SARS-CoV-2 in K18-hACE2 mice
(A–J) Eight-week-old K18-hACE2 mice were inoculated by the intranasal route with 103 PFU of SARS-CoV-2. At 1 (D+1), 2 (D+2), or 3 (D+3) dpi, mice were given 200 μg of COV2-2050 or COV2-2050 LALA-PG by intraperitoneal injection. Naive animals were mock-infected with sterile PBS.
(A and B) Weight change. For (B), statistical analysis was performed only at time points when all mice were alive to avoid survivor bias (mean ± SEM; n = 8–10, 3 experiments).
(C) Survival analysis (n = 8–19, 3 experiments).
(D) Serum concentrations (ng/mL) of COV2-2050 or COV2-2050 LALA-PG at 4 dpi (mean ± SEM; n = 8, 2 experiments).
(E and F) Viral RNA levels at 4 and 8 dpi in the lung (n = 6–10, 3 experiments).
(G) Infectious virus at 4 dpi in the lung (n = 6–8, 2 experiments).
(H) SARS-CoV-2 RNA in situ hybridization of lung sections. Images show low- (top; scale bars, 500 μm) and high-power magnification (bottom; scale bars, 100 μm). Images are representative of n = 4 per group.
(I) Parameters of respiratory mechanics: inspiratory capacity, resistance, elastance, tissue damping, and quasistatic compliance measured at 8 dpi (n = 3–6, 2 experiments).
(J) Pressure volume loops (n = 3–6, 2 experiments).
(A and B) Two-way ANOVA with Sidak’s post-test: ∗p < 0.05, ∗∗∗p < 0.001, ∗∗∗∗p < 0.0001; comparison to the isotype control mAb-treated group. (C) Mantel-Cox log-rank test for survival: ∗p < 0.05, ∗∗∗∗p < 0.0001. (E, F, and I) One-way (E and F) or two-way (I and J) ANOVA with Turkey’s post-test: ns not significant, ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001, ∗∗∗∗p < 0.0001, comparison to the isotype control mAb-treated group.