epitope dominance among CNS-infiltrating CD8 T cells and neutrophil infiltration during acute TMEV infection. Central nervous system (CNS)-infiltrating lymphocytes were isolated 7 days post-Theiler's murine encephalomyelitis virus (TMEV) infection. Shown is fluorescence-activated cell-sorting analysis staining for CD8 and Db: VP2121-130 peptide tetramer among CNS-infiltrating lymphocytes isolated from a representative (A) C57BL/6 mouse or (B) 129 SvIm mouse. (C) CNS-infiltrating C57BL/6 lymphocytes stained for CD8 and negative control Db: E7 peptide tetramer. (D) C57BL/6 and 129 Svlm mice display comparable levels of brain-infiltrating CD45+ cells that are CD8+ and specific for the Db: VP2121-130 epitope. (E) Equivalent capacity of CNS-infiltrating cytotoxic T lymphocytes isolated from TMEV-infected C57BL/6 and 129 SvIm mice to utilize perforin to kill VP2-transfected C57SV target cells in a chromium release assay. Untransfected C57SV cells served as a negative control. CD45hi population was gated and analyzed for the percentage of Ly6G+ cells in both (F) C57BL/6 and (G) 129 Svlm mice (n = 5 per group). (H) Bar chart showing that C57BL/6 and 129 Svlm mice display comparable levels of Ly6G+ cells, which are indicative of being a neutrophil subset. In 1 million isolated total cells recorded by flow cytometry, there were no statistically significant differences in CD45+, Ly6G+, or CD8+ Db: VP2121-130 tetramer-positive cells collected (data not shown).