Fig. 3

The production of cytolytic mediators of HTNV-specific CD8⁺T-cells in HLA-A2.1/K^b Tg mice after peptide immunization. The Tg mice were divided into five groups, including the mice immunized with HTNV linear multi-epitope peptide PADRE-VV9, HLA-A*02-restricted single HTNV-GP CTL epitope VV9, HLA-B*35-restricted HTNV-NP CTL epitope VY9, HTNV-inactivated vaccine and PBS injection, respectively. a Representative flow cytometric plots of cytotoxic mediator granzyme B-producing CD8⁺ T-cells in splenocytes of the Tg mice after three immunizations in different groups. The numbers indicate the percentage of cells within the boxed regions. b Comparison of the percentage of granzyme B⁺ CD8⁺ T-cells (y-axis) among the five different mice groups (x-axis). Peptide VY9-immunized mice were used as an unrelated peptide control, HTNV-inactivated vaccine-immunized mice were used as a positive control and PBS-administered mice were used as a negative control, respectively. The bar in each group represents the mean value ± standard error of mean (SEM). For the gating strategy, splenocytes were defined as FSC/SSC, and CD8⁺ T-cells were defined as CD3⁺CD8⁺ events, displayed on a dot plot of CD8 versus granzyme B. The unpaired t test was used for statistical evaluation. PBS, phosphate buffer saline. VV9, VMASLVWPV. VY9, VPILLKALY. PADRE, AKXVAAWTLKAAA, X = cyclohexylalanine. *P < 0.05