TGFB1 and idiopathic pulmonary fibrosis: To evaluate the activity of TAM inhibitors during fibroblast–myofibroblast transition, HPFs and IPF FBs were treated for 48 h with R428 (1 μM) (concentration that showed relevant results in the proliferation assay; Figure 3c,d) and TGF-β (10 ng/mL), alone or in combination with either R428 (0.1 μM), R428 (1 μM), or LDC1267 (1 μM), and the gene expression of fibrosis-associated markers was evaluated by RT-qPCR (Figure 5).