SOAT1 and infection: To assess whether the absence of ORF3a contributed to the increased sensitivity of viral replication to IFN-α in AAT cells, these cells were treated with the JAK-STAT signalling inhibitor ruxolitinib during infection with rSARS-CoV-2, rSARS-CoV-2-Δ3a-mNG and rSARS-CoV-2-Δ3a-mS.