FIG 5.

MCL1 transgenic mice exhibit an increased number of B8R-specific CD8⁺ T cells during recall in response to a secondary challenge. Mice were infected with VV-WR, and at 55 days after receiving primary infection, they were administered 2 × 10⁶ CFU of L. monocytogenes expressing the B8R epitope. At 7 days after a secondary challenge, their spleens were harvested. (A) Splenocytes were stained with B8R tetramer and anti-CD8 antibody and analyzed by flow cytometry. The percentages of B8R-specific cells shown are those within the CD8⁺ gate. (B) Splenocytes were restimulated with B8R peptide for 5 h in the presence of brefeldin A. Intracellular staining was performed to measure the percentage of CD44⁺ CD8⁺ T cells that were IFN-γ⁺, the percentage of IFN-γ⁺ CD8⁺ cells that were TNF-α⁺, the GzmB mean fluorescence intensity in IFN-γ⁺ CD8⁺ cells, and the percentage of IFN-γ⁺ CD8⁺ cells that were IL-2⁺. The data shown are representative of two independent experiments with four mice per experiment. **, P < 0.001 (for the difference between transgenic [TR] and nontransgenic [Non TR] animals; Student's t test).