FIG 3.

Effect of IL-22 supplementation on pulmonary gene expression and barrier functions. (A to C) Transcriptomic signature of IL-22 in the lungs of IAV-infected mice. Mice were i.n. infected with 500 PFU of the H1N1 pandemic IAV strain. At 7 days postinfection, mice were treated with PBS, the isotype control (5 μg/animal), or IL-22-Fc (5 μg/animal). Lung samples were collected 8 h later for further transcriptomic analysis. Ontological analysis is shown in panel A. Significantly enriched pathways are represented as a bar plot (IPA). Data from four mice are shown. In panels B and C, heat maps show genes that were differentially regulated by IL-22 treatment and that belong to the epithelial growth and proliferation family (GO:0050673) and to the tissue integrity family. Representative genes are noted on the right. Each column represents data from one individual mouse, with four mice per group. (D) Protein concentrations in the BAL fluids of IAV-infected mice treated with IL-22-Fc or IgG. Data represent the means ± standard deviations (n = 10 to 12; three pooled experiments). (E) IAV-infected mice, untreated or treated with IL-22, were inoculated with FITC-dextran. One hour later, FITC-dextran was quantified in the blood. Data represent the means ± standard deviations (n = 8; two pooled experiments). *, P < 0.05; ***, P < 0.001 (Kruskal-Wallis one-way ANOVA).