Figure 6. EC-expressed HGF stimulates lung alveolar regeneration and resolves fibrosis.

(A) Schema illustrating the strategy to test lung alveolar regrowth after pneumonectomy (PNX).

(B–D) Lung MDA quantity (B), Western blot and quantification (C) and immunostaining (D) of NOX4 protein the lung of Hgf^iΔEC/iΔEC and control mice after PNX. n = 10 Hgf^iΔEC/iΔEC and 16 controls. Insets show the distribution of NOX4 protein in the lungs. Statistical difference between experimental groups was assessed by two tailed t-test.

(E–F) Western blot (E) and quantification (F) of NOX4 protein in human and mouse lung fibroblasts treated with 20 ng/ml TGF-β ± 40 ng/ml HGF. n = 6 samples per group. Statistical difference was determined by one-way ANOVA followed by Tukey’s test.

(G) Western blot of NOX4 protein in human lung fibroblasts incubated with EC^HGF or EC^Srb.

(H) Representative immunofluorescence image of human lung fibroblasts (green) co-cultured with human EC^HGF or EC^Srb (red) and treated with 10 ng/ml TGF-β.

(I) Correlation between perivascular NOX4 protein quantity and lung fibrosis score in human patients. Each dot in the plot represents data from individual patient.

(J–L) Representative immunostaining image of samples from (I). Insets show the higher magnification. Sale bars, 50 μm.