TRAF3−/− MEF showed a significant reduction of IFN-β mRNA levels at 24 hours and 48 hours post infection (7.8-fold, P<0.0001 and 2.4-fold, P<0.05, respectively), which was confirmed by measuring IFN-β in the cell supernatant (3.7- and 1.4-fold decrease, respectively, P<0.0001) (Fig 11B and 11D). Here, IFNB1 is linked to infection.