Figure 1. Broadly reactive anti-alphavirus mAbs protect against lethal VEEV challenge.

(A-C) BALB/C were administered 200 μg of SKT05, SKV09, a positive control antibody (1A3B7), or control antibody at 1 h post-aerosol challenge with 10³ PFU of VEEV strain Trinidad Donkey (TrD). Mice were monitored for 14 days for survival (A), weight-loss (mean ±SEM) (B), and clinical score (mean ±SEM) (C) (n = 10 mice/group; 2 independent experiments). (D-F) C3H/HeN mice received 200 μg of indicated mAb 1 day prior to intranasal challenge with 10⁷ FFU of VEEV strain TC-83 (n = 10/group; 2 independent experiments). (D) Survival was followed for 14 dpi. Brains were harvested from a separate group of mice at 1, 3, and 6 dpi and viral RNA (E) or infectious virus (F) was determined by RT-qPCR or FFA, respectively. Bars represent the median. Statistical significance was determined by a Log-rank test (A, D), one-way ANOVA with a Dunnett’s post-test of area under the curve (AUC) analysis from 0–5 dpi comparing each treatment to the control group (B-C), and Kruskal-Wallis with a Dunn’s post-test comparing all groups (E-F). The dotted line indicates starting body weight (B) 940 or the limit of detection (LOD; E-F).