EIF2AK2 and viral infectious disease: Some previous reports suggested that 293T cells expressing the SV40 large-T antigen or a PKR inhibitor (2-aminopurine, 2-AP) might support the replication and propagation of the AdΔVR vector as follows: the SV40 large-T antigen which antagonizes the translational inhibitory effect resulting from the activation of PKR in SV40-infected cells resulted in counteraction of cellular defense against virus infection [100]; 2-aminopurine (2-AP) interferes with the gene induction normally triggered by IFN, and supports the amplification of a VA-RNA-deleted mutant Ad (Sub720) [78,101].