Fig. 3
Anti-envelope antibodies can protect ferrets against lethal SFTSV challenge. a Immunization schedule (Supplementary Fig. 1c shows a detailed timeline of vaccination and immune analysis). b T-cell immunogenicity of SFTSV DNA vaccines in ferrets. IFN-γ ELISpot assays were performed to detect antigen-specific IFN-γ-producing T cells by stimulating PBMCs from vaccinated or non-vaccinated (control) ferrets with OLP pools covering Gn and Gc. Data represent the average number of SFUs per 2 × 105 PBMCs. c Neutralizing antibody response to SFTSV CB1/2014 strain (genotype B) generated in ferrets by DNA vaccines (pVax1-Gn and pVax1-Gc, blue bars and symbols) or serum transfer (green bars and symbols). The amount of neutralizing antibody against SFTSV was determined based on FRNT50. d Survival of non-vaccinated control (n = 6, red line), Gn/Gc-vaccinated (n = 4, blue line), and Gn/Gc serum-transfered (n = 4, green line) ferrets after lethal SFTSV challenge. e Survival of control serum-transferred (n = 3, orange line) and N/NSs/RdRp serum-transferred (n = 3, light blue line) ferrets after lethal SFTSV challenge. f Circulating viral titers in non-vaccinated control (red bars, symbols and line), Gn/Gc-vaccinated (blue bars, symbols, and line), and Gn/Gc serum-transferred (green bars, symbols, and line) ferrets after SFTSV challenge. g Platelet counts in non-vaccinated control (red bars, symbols and line), Gn/Gc-vaccinated (blue bars, symbols, and line), and Gn/Gc serum-transferred (green bars, symbols and line) ferrets after SFTSV challenge. The normal platelet count range in ferrets is 171.7–1280.6 × 103 per μL. Dashed lines indicate the normal platelet count values. Data are presented as mean ± s.e.m. Asterisks next to the symbols on graphs indicate significance between vaccinated and control ferrets per dpi. Asterisks next to the group labels indicate significance between groups indicated. Statistical significance was determined by two-tailed Mann–Whitney U-test (b, c), log-rank (Mantel-Cox) test (d, e), or two-way ANOVA test with Sidak correction (f, g). *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001. Source data are provided as a Source Data file
