Fig. 2: RVFV-specific antibodies are largely dispensable for survival in the presence of pre-existing RVFV-specific T cells.

Mice (n = 10 per experimental group) were depleted of CD20+ lymphocytes or mock-depleted, then vaccinated with 2 × 10⁵ TCID₅₀ DelNSsRVFV. Half were euthanized for immune assessment, and the other half were challenged with 2 × 10⁵ TCID₅₀ of WT RVFV (A). Animals were monitored for survival (B). Endpoint titers of RVFV-specific antibodies by ELISA (C) or neutralizing antibody titers (D) were measured 22 days after vaccination/prior to WT challenge, and again at the end of the experiment. The dotted line is the LOD (100 for ELISA, 40 for FRNT₈₀). Negative values were plotted at 50 and 20, respectively. The geometric mean titer is noted for each group. The number of RVFV-specific T cells in total splenocytes was determined by IFN-γ ELISPOT assay, expressed as the number of spots per 1 × 10⁵ splenocytes (n = 3, in duplicate) (E). Mean and standard deviation are noted.