ISLR and pulmonary fibrosis: Similar to the cancer stroma, we found the proliferation of Meflin-positive cells and their lineage cells in the hearts after acute myocardial infarction (MI) and pressure-overload heart failure mouse models as well as in fibrotic foci of pulmonary fibrosis in humans and mice (Hara et al., 2019; Nakahara et al., 2021).