Only a fraction of COL1A1 and CTHRC1 positive cells co-expressed with ACTA2 (gene of αSMA protein) in human idiopathic pulmonary fibrosis and scleroderma, implying the clinical existence of other ‘non-classic’ fibroblast phenotypes involved in fibrosis [72]. The gene discussed is CTHRC1; the disease is pulmonary fibrosis.