SFRP2 and idiopathic pulmonary fibrosis: Our data is in line with previous reports of several IPF pathogenic pathways, namely the WNT pathway38,39 (e.g. FZD5, SFRP1, SFRP2) and migratory associated processes40–42 (e.g Thy1, MMP13, ADAMTSL3) that respond to the IPF environment.