Fig. 7.

SPI-2 protein reduces the size of cytotoxic lymphocyte populations in mousepox infection. BALB/c mice infected s.c. with 10³ PFU of each virus were sacrificed at 6 days p.i. Spleens and blood were harvested for FACS staining. (A) Total numbers of CD8⁺ splenocytes. (B and C) Percentages of CD8⁺ cells found in the spleen and blood, respectively. (D) Percentages of granzyme B⁺ CD8⁺ cells. (E) Total numbers of DX5⁺ splenocytes. (F) Percentages of DX5⁺ cells in the spleen and blood. (G and H) Percentages of granzyme B⁺ DX5⁺ cells. (I) Total numbers of DX5⁺ and granzyme B⁺ splenocytes. The graphs are the means ± SEM of data pooled from three independent experiments (A, B, and D to G) or two independent experiments (C, H, and I) (n = 3 for each experiment). *, P < 0.05; **, 0.001 ≤ P ≤ 0.01; and ***, P < 0.0001 in relation to both wt ECTV and ECTV SPI-2 REV. (J to M) Representative flow cytometry plots of blood lymphocyte samples from mice infected with ECTV SPI-2 SAD^Δ (J, L, and M) or ECTV (K) shown in the bar graph in panel G. The background staining of preimmune rabbit serum was used for gating granzyme B⁺ populations (J), and NK cell-depleted blood lymphocytes were used for gating DX5⁺ populations (M).