Conversely, however, but consistent with our IFN-β treatment assay, MX1, IFIT1, and ISG15 transcript levels were significantly higher in A549 cells as compared to SC (Figure 4C), indicating that even though ZIKV infection triggered higher IFN induction, it did not translate into stronger downstream IFN signal transduction. Here, MX1 is linked to Zika virus infectious disease.