(A) NP(366–374)-specific CD8+ T cells stain positive for caspase 3, as a marker of apoptosis, after anti-CD27L monoclonal antibody treatment in the late phase of the primary CD8+ T cell response to influenza infection. FACS plots are shown, indicating percentages of NP(366–374)-specific CD8+ T cells staining positive for active caspase 3 on day 7 post virus infection, in the lung of animals treated on day 6 post infection with anti-CD27L antibody or left untreated.
(B) Pooled percentages of antigen-specific CD8+ T cells staining positive for active caspase 3 in untreated animals (solid bar) or animals treated with anti-CD27L antibody (cross-hatched bar) on day 6 post infection, shown. Bars mark the average percentage (± SEM) of 6 mice from each treatment group, on day 7 post infection.