Analysis of CD8+ T cells at day 9 in the spleen of wild type mice treated with the MAR1-5A3 or control antibody at day 4 after infection showed a similar percentage and total number of WNV-specific CD8+ T cells when measured by intracellular IFN-γ and TNF-α staining after ex vivo incubation with an immunodominant Db-restricted NS4B peptide (Figure 2A) or direct tetramer staining (data not shown). Here, TNF is linked to infection.