Fig. 5: AMs initiate matrix transfer by activating mesothelium through IL-18.

a Representative immunolabeling histology images of IL-18 receptor expression in murine and human IPF lungs. n = five biological replicates (C57BL/6J WT mice) and 3 independent experiments. Scale bars: 50 µm (murine); 20 µm (human). b Representative immunolabeling histology image of IL-18 expression in lungs 1, 7, 10 and 14 days p.b.i. or 15 days post-herpes virus installation. n = 3 biological replicates (C57BL/6J WT mice) and 3 independent experiments. Scale bars: 100 µm(10x); 50 µm(20x). Data represented are mean ± SD. A two-sided independent T-test was used for the comparison of two groups (p.b.i.: Day 1:p = 0.000138, Day 7:p = 0.000663, Day 14:p = 0.0004998)(post-herpes virus: Day 15: p = 8.34e-05, Day 45: p = 7.34e-06)(***P < 0.001). c Representative immunolabeling histology image showing contrast of IL-18 expression in lung interstitium compared to surface 14 days p.b.i. n = five biological replicates (C57BL/6J WT mice) and 3 independent experiments. bars: 50 µm. d Representative immunolabeling histology images against IL-18 in combination with CD45 and CD11c in lungs 14 days p.b.i. or human IPF lung tissue. n = 3 biological replicates (C57BL/6J WT mice) and 3 independent experiments. Data represented are mean ± SD. A two-sided independent T-test was used for the comparison of two groups (***P < 0.001). Scale bars: 50 µm. e Representative histology images of mouse lung tissue with NHS-FITC⁺ marked pleural site cultivated ex vivo with 10 ng/ml recombinant IL-18 or in trans wells with macrophages and 100 ng/ml IL-18 Receptor-blocking antibody for 48 h. Data represented are mean ± SD. n = five biological replicates and 6 independent experiments. One-way ANOVA was used for the multiple comparison (***P < 0.001). Scale bars: 25 µm. f Flowchart of ex vivo mouse lungs coculture with IL-18+ macrophages using transwell. Created in BioRender. Han, W. (2024) https://BioRender.com/y450579.