CASP3 and Sepsis: To rule out the possibility that the numerical loss of CD45.2+ CD8 T cells in the CLP-treated mice was a result of cell redistribution within the host, we found a significant increase in the frequency of CD45.2+ lung vasculature CD8 T cells with activated caspase-3/7 in CLP- versus sham-treated mice (S3L–S3N Fig) suggesting sepsis leads to apoptosis of circulatory memory CD8 T cells.