Figure 2.

Inoculation with CHIKV-NoLS CAF01 elicits de novo viral particle production and disease in AG129 mice. AG129 mice were inoculated with viable virus/vaccine particles (10⁴ pfu CHIKV-WT or CHIKV-NoLS) or CAF01 delivered RNA (2 μg CHIKV-WT or CHIKV-NoLS RNA complexed with 0.3 mg CAF01) in the ventral/lateral side of the right foot. Mock inoculated mice received 20 μl VPSFM media or VPSFM media containing 0.3 mg CAF01. (A) Serum was collected on days 1–6 post inoculation and virus titrated by plaque assay. Survival curves were constructed (B) as mice were monitored for the development of disease signs (C) and changes in weight (D) every 24 h. Disease signs in inoculated AG129 mice were scored on a scale of 0–4 where 4 is humane endpoint. (E,F) CHIKV-induced footpad swelling was assessed by measuring the height and width of the perimetatarsal area of the foot, using Kincrome digital vernier calipers. Each symbol represents the mean ± standard error from five to six mice. Statistical analysis was performed by non-parametric Mann–Whitney t-test between the groups indicated on the figure legend by the bar and *color. ns, not significant,*P < 0.05, **P < 0.005, ***P < 0.001, and ****P < 0.0001.