Figure 1. IL-37 reduces inflammatory cell recruitment in mice with inflammatory aspergillosis.

C57BL/6 mice were infected intranasally (in) with A. fumigatus and pretreated one time with different doses IL-37 administered intraperitoneally (ip) at different times before the infection. Mice were assessed for: (A) fungal growth (Log₁₀ CFU, mean±SD) in the lungs at 1 and 3 days post-infection (dpi); (B) BAL fluid morphometry [number of total (T) cells and polymorphonuclear neutrophils (P) upon May Grunwald Giemsa staining. Values represent the mean±SD of three mice per group and are representative of 3 independent experiments]; (C) lung histology (periodic acid-Schiff and, in the inset, TUNEL staining). Red arrows indicate PMN and white arrows indicate increased deposition of DNA on lung parenchyma (in TUNEL-stained sections). Scale bars, 25 µm; (D) myeloperoxidase (Mpo), Cxcl1 and Cxcl2 mRNA expression by RT-PCR on total lung cells; (E) lung histology (periodic acid-Schiff staining, scale bars, 25 µm) and (F) Mpo, Cxcl1 and Cxcl2 mRNA expression (RT-PCR on total lung cells) in mice pretreated with IL-37 given ip or in, at different hours before the infection. (G) Numbers of CD11b/Gr1–positive cells were assessed by flow cytometry of total lung cells from LPS-treated mice. Data are representative (histology) or pooled from three experiments. *P<0.05,**P<0.01, treated vs untreated (None) mice. Naïve, uninfected and untreated mice.