Early after LCMV infection, Blimp1 expression was increased in KLRG1hi/intCD127lo cells, which also showed the expression of genes associated with effector functions of TRM cells, such as elevated levels of granzyme B. On the other hand, KLRG1loCD127hi small intestinal CD8+ T cells expressed high levels of Id3 rather than Blimp1 and they shared their transcriptional signatures with the other memory, or memory-like, cells, including TCM and TFH cells in the effector phase and TRM cells in the memory phase of infection. This evidence concerns the gene PRDM1 and infection.