Increased expression of the extracellular matrix protein Tenascin‐C, which is a known marker in tissue repair and was also upregulated in mouse lung injury (Appendix Fig S6F), was found in IPF tissue sections in KRT5+ basal cells in the “bronchiolized” distal lung (Fig 6G). This evidence concerns the gene KRT5 and idiopathic pulmonary fibrosis.