In an experiment with mice infected with recombinant TMEV, mice lacking the Kb LoxP class I molecule (the key molecule for antigen presentation to CD8 T cells) exhibited significantly higher viral loads in the CNS at 7 days post‐infection compared to controls, and brain lymphocyte infiltration was also significantly mitigated, suggesting that the absence of APCs impairs the response of CD8 T cells to viral infection [7]. This evidence concerns the gene CD8A and viral infectious disease.