FIGURE 4.

Arm/07/CBM/c2 and NH/P68 interfere with IFN-I signaling by targeting STAT1 and STAT2. PAMs were mock infected or infected with either Arm/07/CBM/c2 (A) or NH/P68 strain (B) (2 PFU/cell) for 8 or 16 h, in absence or in presence of AraC (40 μg/ml). At 7 or 15 hpi, PAMs were stimulated or not with universal type I IFN (1,000 U/ml). After 1 h of stimulation, cells were collected and lysed in RIPA buffer for further analysis by Western blot. Antibodies against pSTAT2, STAT2, pSTAT1, STAT1, IRF9, early viral protein p32, and actin were employed. As a control of AraC effect on viral DNA replication, a specific antibody against the late viral p17 protein was used, which is only expressed in the absence of AraC.