CD8A and viral infectious disease: Priming of both CD4+ and CD8+ T cells requires type I IFN signaling (10, 72, 73), and CD4+ and CD8+ T cell recruitment was shown to be impaired in type I IFN receptor α1 chain-deficient (CD118−/−) mice infected with HSV-1, pointing to a major role for type I IFN in the modulation of T cell priming during viral infection (74).