Fig. 2: VSV-CCHFgpc vaccination induces significant B cell and T cell responses.

Six-week-old C57BL/6J mice were vaccinated intraperitoneally with 1 × 10⁴ PFU VSV-CCHFnp1 or VSV-CCHFnp2 or VSV-CCHFgpc or VSV-EBOV on day -28. On day 0, groups of six mice were euthanized and blood and spleen samples were collected for evaluation of immune responses. Whole virion ELISA (a) or specific isotypes (b) was used to detect IgG responses elicited by the CCHFV-NP vaccines. c CCHFV-Gc specific IgG antibodies were evaluated by recombinant ELISA or d specific isotypes. CCHFV-GP38-specific IgG antibodies were evaluated by recombinant ELISA (e) or specific isotypes (f). Dashed line represents the cut-off for seropositivity, which was set at 3 standard deviations above the mean absorbance of wells that received no serum. g, h CCHFV-specific T cell responses were measured using IFN-γ ELISpot. The number of spot-forming cells against individual CCHFV-NP (g) or GPC peptide pools (h), the mitogen concanavalin A or DMSO vehicle alone are shown. Statistical significance was calculated using one-way ANOVA with Tukey’s multiple comparisons test (a, c, e) or two-way ANOVA with Sidak’s multiple comparisons test (b, d, f, g, h) and results are indicated as *p < 0.05, **p < 0.01, and ***p < 0.001. Comparisons with p values >0.05 were not displayed. Data shown as geometric mean plus standard deviation.