P4ha2

The Click-iT® EdU Alexa Fluor® 488 Imaging Kit and Alexa Fluor® 594 phalloidin were from Invitrogen. Matrigel (lrECM) and Type I collagen were from BD Bioscience. ShP4HA2 plasmids were purchased from Sigma. 1, 4-DPCA was purchased from Cayman Chemical. Masson’s trichrome stain kit was purchased from Polysciences, Inc. The following antibodies were obtained as indicated: integrin α6 (Millipore); collagen I (Abcam); collagen IV (Abcam); P4HA2 (Santa Cruz); tubulin (Millipore).

Murine lungs were collected, fixed with formalin and embedded in paraffin. Histological sections were deparaffinized, hydrated and exposed to epitope antigen retrieval with ER solution (DAKO, pH6), followed by endogenous peroxidase activity blocking for 5 min. After protein blocking (DAKO) for 60 min, sections were stained with primary antibodies, using a previously optimized dilution Nanog (4903S, Cell Signaling, dilution 1:100), YAP (4912, Cell Signaling, dilution 1:100), P4HA2 (sc‐161146, Santa Cruz Biotechnology, dilution 1:50), TTF‐1 (MA5‐13962, Thermo Scientific, dilution 1:100), Mucin 5B (sc‐20119, Santa Cruz Biotechnology, dilution 1:50) overnight in 4C. After washing, sections were incubated in secondary antibodies using EnVision detection kit (DAKO) for 30 min in room temperatures, rinsed counterstain with haematoxylin and mounted on glass slides. Slides were imaged by using Aperio ScanScope CS slide scanner, and evaluated for and percentage (0–100%) of nuclear intensity score (0, none; 1, weak; 2, moderate; and 3, strong) by using ImageScope software (Aperio).