PRRX1 and pulmonary fibrosis: In the present study, we further characterized the Prrx1-positive mesenchymal cells in the bleomycin preclinical mouse model of lung fibrosis using a lineage tracing approach (Homps-Legrand et al., 2023) with a Prrx1:CreERT2; Rosa26iTomato transgenic mouse line (Kawanami et al., 2009).