FIG 7.

Adaptive, VACV-specific T cell immune responses. Splenocytes were collected from mice (5 per group) immunized with MVA-WT/MVA-WT or MVA-CHIKV/MVA-CHIKV 10 days after the last immunization. Next, adaptive, VACV-specific CD4⁺ and CD8⁺ T cell immune responses triggered by both immunization groups were measured by ICS assay following stimulation of splenocytes with MVA-infected EL4 cells. Values from unstimulated controls were subtracted in all cases. Data are from one experiment that is representative of two independent experiments. (A) Overall magnitude of VACV-specific CD4⁺ and CD8⁺ T cells. The values represent the sums of the percentages of T cells producing CD107a and/or IFN-γ and/or TNF-α and/or IL-2 against MVA-infected EL4 cells. (B) Percentages of VACV-specific CD8⁺ T cells producing CD107a, IFN-γ, TNF-α, or IL-2. Frequencies represent percentages of CD8⁺ T cells producing CD107a, IFN-γ, TNF-α, or IL-2 against MVA-infected EL4 cells. (C) Functional profiles of adaptive, VACV-specific CD8⁺ T cell immune responses. All the possible combinations of the responses are shown on the x axis (15 different T cell populations), while the percentages of CD8⁺ T cells producing CD107a and/or IFN-γ and/or TNF-α and/or IL-2 against MVA-infected EL4 cells are shown on the y axis. Responses are grouped and color coded on the basis of the number of functions (4, 3, 2, or 1). The pie charts summarize the data. Each slice corresponds to the proportion of VACV-specific CD8⁺ T cells exhibiting one, two, three, or four functions within the total population of VACV-specific CD8⁺ T cells.