To determine whether the ribonucleoprotein complex MiCEE25, in which Mirlet7d is functionally relevant, mediates epigenetic silencing in humans as it does in mice, we performed various experiments using primary fibroblasts isolated from lung tissue from Ctrl (n = 3) and IPF (n = 3) patients (Supplementary Fig. 1b). This evidence concerns the gene MIRLET7D and idiopathic pulmonary fibrosis.