Collagen triple helix repeat containing 1 (Cthrcl) positive pathologic fibroblasts expand in both pathologies (though to a greater extent in pulmonary fibrosis) and are enriched for LTBP2 expression compared to other fibroblast populations (Fig 1A-D, S1A,B), though LTBP2 expression per cell is generally unchanged with disease in these datasets (not shown). This evidence concerns the gene CTHRC1 and pulmonary fibrosis.