Fig. 2.

Effects of JAK2 and STAT3 on ATII to mesenchymal and fibroblast to myofibroblast transitions. Primary ATII and lung fibroblasts were isolated from the lungs of IPF patients. a The cells were incubated with the dual p-JAK2/p-STAT3 inhibitor JSI-124 for 30 min followed by TGF-β1 stimulation for an additional 24 h. IL-6 and IL-13 levels in cell supernatants were measured using ELISA. b Ratios of JAK2/p-JAK2 and STAT3/p-STAT3 were determined by western blotting in ATII cells stimulated for 40 min or 24 h with TGF-β1 in the presence or absence of JSI-124. c, d ATII cells were pre-incubated for 30 min with 1 μM of the p-STAT3 inhibitor 5,15 DPP, the p-JAK2 inhibitor NSC33994, or the dual p-JAK2/p-STAT3 inhibitor JSI-124, and then stimulated for 72 h with TGF-β1 (c) or IL-6/IL-13 (d). e Levels of IL-6 and IL-13 in primary fibroblasts. f JAK2/p-JAK2 and STAT3/p-STAT3 protein expression in human lung fibroblasts. g, h Primary lung fibroblasts pre-incubated for 30 min with 1 μM of the p-STAT3 inhibitor 5,15 DPP, the p-JAK2 inhibitor NSC33994, or the dual p-JAK2/p-STAT3 inhibitor JSI-124 and stimulated for 72 h with TGF-β1 (g) or IL-6/IL-13 (h). Representative western blots are shown. The results are expressed as the mean (SEM) of n = 4 (cells from four IPF patients) experiments per condition. Two-way ANOVA followed by post-hoc Bonferroni tests. *P < 0.05 vs. the solvent controls; ^#P < 0.05 vs. TGF-β1 or IL-6/IL-13; ┴ P < 0.05 vs. 5,15 DPP or NSC33994