IFNB1 and infection: Further examination of IFN-β production in A549 cells in response to infection with these viruses showed that recombinant rTCRV-WT, after producing a slight transient increase in IFN-β mRNA transcription at 4 hours post-infection (hpi), was able to successfully suppress upregulation of IFN-β transcription, which then increased only gradually during the time-frame from 24–72 hpi (Fig 6B).