Fig. 2: Vaccination with lower doses of live attenuated RVFV ΔNSsΔNSm still protects CC057/Unc mice against lethal RVF encephalitis.
Mice (n = 3 per experimental group) were vaccinated with either 20 TCID50 or 2000 TCID50 of ΔNSsΔNSm RVFV and then challenged at 28 days post-vaccination with 2 TCID50 WT RVFV, both via foot pad injection (A). Animals were monitored for survival, and survivors were euthanized on day 56 post-vaccination (B). Terminal viral RNA loads in liver, spleen and brain were measured for the L and S segment for vaccinated animals and samples from Mock infected animals from Fig. 1 were included for comparison (C, D). The dotted lines represent the LOD of the assays (L segment: 3.6 x 106 copies/g; S segment: 8 x 106 copies/g). Data points marked with x indicate that no virus could be isolated from brain tissues while the data point with the check indicates that virus could be isolated from brain tissue (C). The endpoint titers of total RVFV-specific or RVFV NSs-specific antibodies by ELISA or neutralization titers were measured pre-challenge (E, F) and at the time of euthanasia (G, H). The LOD is depicted as a dotted line at 100 for ELISA and 40 for FRNT80. Negative values were plotted at 50 for ELISA. Survivors are displayed as open symbols, and graphs depict the geometric mean and SD for each group. The timeline (A) was generated using BioRender.com.
