NT5E and infection: In both C57BL/6 and CD73−/− mice, βgal96-specific CD8+ T-cells gradually increased after infection, over the course of 50 days, while βgal497-specific CD8+ T-cells increased in frequency to 10% of total CD8+ T-cells at 14 days post infection and then gradually declined, being maintained thereafter at a low but stable frequency (Figure 5C).