CD4 and Sepsis: PD-1 expression was quantitated in the two-hit model of sepsis as well.PD-1 expression was increased on CD4 and CD8 T cells at Day 3 following CLP (prior to Candida infection).CD4 T cell PD-1 expression was also increased at days 9 and 12 following CLP which corresponds to days 6 and 9 following the second-hit Candida infection (Figure 3C).CD8 T cell PD-1 expression was increased at Day 5 post CLP which corresponds to Day 2 following the second-hit Candida infection but not at other times (Figure 3D).