IFNLR1 and infection: Infection of control A549 and A549 cells with a loss-of-function deletion of the type I IFN receptor IFNAR either solely (IFNAR KO) or in combination with IFNLR1 (IFNAR/IFNLR1 KO) allowed for the analysis of the antiviral efficacy of endogenous type I and III IFNs that are generated during RuV infection, as shown in our own publication [10].