IRF4 and viral infectious disease: Since chronic, persistent viral infections have often been associated with the development of T-cell exhaustion and we identified a set of TFs that could also be associated with this process (namely EOMES, NFATC2, PRDM1 [BLIMP-1], IRF4 and BATF), we hypothesized that a similar immune process is likely to be involved in the reproductive tract during EAV long-term persistence.