Impaired generation of CD8 memory cells to both dominant and subdominant VACV epitopes in BTLA-deficient mice.

<p>Groups of C57BL/6 WT, BTLA-deficient (BTLA^−/−), or HVEM −/− mice were infected i.p. with the indicated inoculums of VACV-WR (A and B) and VACV-Lister (C and D). At day 64, splenocytes were harvested and stimulated with the indicated VACV peptides and CD8 T cell numbers and functionality was assessed by tetramer and intracellular IFN-γ staining. (A) Representative plots of B8R, A3L, A8R, and A23R tetramer staining, gating on CD8 cells, are shown. Percentages of activated tetramer⁺ CD8 T cells (CD8⁺CD44⁺B8R⁺) are indicated. (A) <i>Right</i>, Total numbers of CD8⁺CD44⁺tetramer⁺ cells per spleen (B) Representative plots of IFN-γ staining in gated CD8⁺CD62L^Low T cells. Percent positive indicated. <i>Right</i>, Total numbers of CD8⁺IFN-γ⁺ cells per spleen. Results are mean number ± SEM (<i>n</i> = 4 mice/group) from one experiment. *<i>p</i><0.05 (WT mice vs gene-knockout) as determined by Student’s <i>t</i> test. Similar results were obtained in two separate experiments.