Cytokine producing ability of PD-1^high and PD-1^medium CD8 T cells during lytic phase of HSV-1 infection.

<p>Mice infected with HSV-1 were euthanized on day 6 post-infection. PLN and spleen tissue obtained were homogenized to obtain singe cell suspension. CD8 T cells were stimulated with immunodominant SSIEFARL peptide and pro-inflammatory cytokine producing PD-1^high and PD-1^medium CD8 T cells were determined by flow cytometery as described in the methods. A and B, Representative FACS plots gated on CD8 T cell and bar diagrams denote the proportion of IFN-γ, TNF-α and IL-2 producing PD-1^medium and PD-1^high CD8 T cells in PLN and spleen on day 6 post-infection, respectively. Data shown is representative of two similar experiments with five mice in each group/experiment. Statistical significance was determined with unpaired student’s t test where *p<0.05, **p<0.01 and ***p<0.0001 were considered significant.