Figure 5. Protective efficacy of human monoclonal antibodies (mAbs) against lethal ebolavirus infection in laboratory mice and domesticated guinea pigs.

(A) Survival of mice treated with 1C3 or 1C11 prior to Ebola virus (EBOV) exposure. mAbs were administered 24 h prior to exposure with 100 plaque-forming units (PFU) of mouse-adapted EBOV. A human immunoglobulin G against influenza A virus (IgG1) mAb was used as a control. Animal survival was assessed twice daily for 21 d. n = 10 mice were studied per treatment condition. (B) Survival of STAT1 KO mice treated with 1C3 or 1C11 after EBOV/BDBV-GP exposure. Groups of STAT1 KO mice at five animals per group were injected with the indicated mAbs by the intraperitoneal route at 24 h after BDBV chimeric virus challenge. Kaplan-Meier survival curve is shown. Each group was compared with phosphate-buffered saline (PBS) control (Mantel-Cox test). (C and D) Groups of guinea pigs at five animals per group were injected with indicated mAbs by the intraperitoneal route at 1 or 3 days after EBOV (C) or Sudan virus (SUDV) (D) exposure. Kaplan-Meier survival curves, body weights, illness score curves, and viremia levels are shown. For analysis of survival, each group was compared to PBS mock control (Mantel-Cox test). In panels representing viremia, each dot corresponds to an individual serum sample. Short horizontal lines indicate the mean value of titers. The dotted horizontal lines show the detection limit. For analysis of viremia data, serum samples collected on different days were pooled together in each experimental group. Samples without detectable virus were arbitrarily assigned the viremia level values corresponding to the detection limit (10² PFU/mL). One-way analysis of variance (ANOVA) with Dunnett correction was used for multiple comparisons between each group and PBS mock control.