Fig. 4
N/NSs/RdRp-specific T-cell responses can protect ferrets against lethal challenge. a 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 N, NSs, and RdRp. Data represent the average number of SFUs per 2 × 105 PBMCs. b Neutralizing antibody response to SFTSV CB1/2014 strain (genotype B) generated by DNA vaccines in ferrets. The amount of neutralizing antibody against SFTSV was determined based on FRNT50. c Survival of N/NSs/RdRp- (n = 4, green line), N- (n = 3, indigo line), NSs- (n = 3, gray line), or RdRp- (n = 3, pink line) vaccinated and non-vaccinated control (n = 6, red line) ferrets after lethal SFTSV challenge. d Circulating viral titers of N/NSs/RdRp- (green bars, symbols and line), N- (indigo bars, symbols, and line), NSs- (gray bars, symbols and line), or RdRp- (pink bars, symbols, and line) vaccinated ferrets after SFTSV challenge. e Platelet counts in N/NSs/RdRp- (green bars, symbols, and line), N- (indigo bars, symbols, and line), NSs- (gray bars, symbols, and line), or RdRp- (pink bars, symbols, and line) vaccinated ferrets after SFTSV challenge. The normal platelet count range in ferrets is 171.7–1280.6 × 103 per μL. Dashed lines indicate 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. ND, not determined due to the sample unavailability. Statistical significance was determined by two-tailed Mann–Whitney U-test (a, b), log-rank (Mantel-Cox) test (c), two-way ANOVA test with Sidak correction (d, e). *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001. Source data are provided as a Source Data file
