Figure 3.

Overexpression of IL-15 in the lung results in significant repression of RARβ during influenza virus (Flu) infection. Wild-type (WT) and IL-15 transgenic (IL-15Tg) mice were infected with Flu. On Day 7 after infection, the mRNA expression of the RA signaling components in the lung was measured using quantitative PCR. The relative mRNA levels of RARα (A), RARβ (B), RARγ (C), RALDH1 (G), RALDH2 (H), and Cyp26b1 (I) are shown (n = 3–5 mice/group). The protein levels of RARα (D), RARβ (E), and RARγ (F) in the lung were assessed using Western blotting. Data are representative of three experiments. *P < 0.05; **P < 0.01.