To generate a well-defined population of CD8+ Tmem cells, we transferred congenically marked OT-I CD8+ T cells, which express a TCR specific for the SIINFEKL peptide of OVA, into WT C57BL/6J animals followed by infection with OVA-expressing vesicular stomatitis virus (VSV-OVA; Figure 1A). This evidence concerns the gene CD8A and infection.