Antibody protection of MAYV-induced musculoskeletal disease. (A) Swelling observed in the ipsilateral (4 dpi, left) and contralateral (7 dpi, right) ankle following infection with MAYV-BeH407. (B–G) Protective mAbs in the lethal challenge model (Fig. 5) were tested for activity against MAYV-induced musculoskeletal disease. 4-wk-old C57BL/6J male mice were given 100 µg of indicated mAbs via intraperitoneal route 1 d before subcutaneous inoculation of 10³ FFU MAYV-BeH407 in the foot. Swelling was measured in the ipsilateral (B, D, and F) and contralateral (C, E, and G) ankles using digital calipers. Data are the mean and SEM of two experiments (n = 10 mice, two-way ANOVA with Tukey’s post-test). (H–M) Virus titers in the ipsilateral (H and I) or contralateral (J and K) feet or draining inguinal lymph node (L and M) at 1 (H, J, and L) and 7 (I, K, and M) dpi after prophylaxis of mice with 100 µg of the indicated mAbs. Animals were perfused with PBS before tissue collection. Viral titers were determined by qRT-PCR. Data are from two experiments (n = 10 mice, one-way ANOVA with Dunnett’s post-test). *, P < 0.05; **, P < 0.01; ***, P < 0.001, ****, P < 0.0001. The experiments in B, D, and F or C, E, and G were performed concurrently, and thus a single isotype control mAbs was used and included in each graph.