FIG 3.

Inhibition of IAV-induced EGFR/ERK signaling upregulates the expression of innate immunity-related genes. A549 cells were pretreated with 1 μM afatinib (Afa) for 12 h, followed by infection with WSN (A and C), PR8 (E), or CA04 (F) (MOI = 1). (B and D) After U0126 treatment at a concentration of 10 μM for 12 h, A549 cells were infected with WSN (MOI = 1). Total RNA was extracted at 8 h postinfection, and the mRNA levels of IFNs and ISGs were determined by qRT-PCR. (G and H) A549 cells were treated with 1 μM Afa or 10 μM U0126 prior to WSN infection (MOI = 1). IFN-β and IL-29 levels in the culture supernatants collected at 15 h postinfection were measured by ELISA. Data are means and SD. *, P < 0.05; **, P < 0.01.