TGFB1 and idiopathic pulmonary fibrosis: Prior to TEM, the cells from one control and from one IPF lung were cultured without serum for 4 days with 5 ng/ml TGFβ1 alone, with TGFβ1 and 0.5 mM pirfenidone, with TGFβ1 and 0.5 μM nintedanib or without any added compounds.