Figure 5.

Listeria-infected knockout mice retain wild-type levels of bacteria-specific CD8 T cells making interferon (IFN)-γ. Mice were infected and challenged as described in Fig. 4. (a) The bar graph shows the ratio of total IFN-γ-producing (open bars) or tumour necrosis factor (TNF)-α-producing (black bars) CD8 T cells in infected mice to those in naïve mice of the different strains, as indicated. Cells were gated as 7-aminoactinomycin D (7AAD)⁻, T-cell receptor (TCR) αβ⁺, CD4⁻, CD8α⁺, cytokine⁺ cells. (b) The bar graph indicates the ratio of ovalbumin (OVA)-specific IFN-γ-producing (open bars) and TNF-α-producing (black bars) CD8 T cells in infected mice to those in naïve mice. Values for both naïve and infected mice were obtained by multiplying the fraction of cytokine⁺ OVA⁺ CD8⁺ T cells by the percentage of IFN-γ⁺ or TNF-α⁺ CD8⁺ T cells. No significant differences between any knockout strain and wild-type mice were detected in the statistical analysis in the data shown in (a) or (b).