*4.2. Study Approval*

Healthy donor lung tissue explants from Lund University hospital (Lund, Sweden) and lung samples from patients diagnosed with IPF were received from Sahlgrenska University hospital (Gothenburg, Sweden). The study was approved by ethical committees in Lund and Gothenburg, Sweden (Dnr. 413/2008, 2015-891, and 1026-15). Written informed consent was received from participants or the closest relative.
