Protein and Signaling Pathway Analysis

Protein extraction and western blot assays were conducted as previously described^{39 (link)}. The primary antibodies against α-SMA (ab7817, 1:300 dilution), collagen I (ab138492, 1:1000 dilution), GAPDH (ab8245, 1:5000 dilution), Smad3 (ab40854, 1:1000 dilution) and phospho-Smad3 (Ser 423 and Ser 425, ab52903, 1:1000 dilution) were purchased from Abcam (MA, USA); STAT6 (#9362, 1:1000 dilution), phospho-STAT6 (Tyr641, #9361, 1:1000 dilution), Akt (#9272, 1:1000 dilution), phospho-Akt (Ser473, #9271, 1:1000 dilution), ERK 1/2 (p44/42 MAPK, #4695, 1:1000 dilution) and phospho-Erk1/2 (Thr202/Tyr204, #4370, 1:1000 dilution) from Cell Signaling Technology (MA, USA) and IL4Rα (YT2337, 1:1000 dilution), TGFβ RI (YT4627, 1:1000 dilution) and TGFβ RII (YT4628, 1:1000 dilution) from ImmunoWay (TX, USA).