EIF2A and infectious mononucleosis: To confirm that LMP1 expression is sufficient to block the ISR pathway in ΔLMP1 EBV- infected NOKs, ΔLMP1 EBV-infected NOKs were stably infected with a control lentiviral vector, or a lentivirus expressing LMP1 from the type 1 EBV strain B95.8 (derived from a mononucleosis patient in the USA) [20], and the effect on eIF2α phosphorylation and other ISR pathways markers was examined.