TGFB1 and cystic fibrosis: Compared with 12 and 24 h of incubation, the maximal expression of α-SMA protein was found at 48 and 72 h following stimulation with 5 ng/ml TGF-β1 (Fig. 2C and D) Therefore, we selected 5 ng/ml TGF-β1 with 48 h of incubation to induce CF transformation into myofibroblasts.