PDGF-enriched microenvironment would also contribute to tissue fibrosis as seen in Duchenne muscular dystrophy (DMD), where PDGFRα + Sca1 + CD45− mesenchymal progenitor cells would be activated into tissue remodeling cells after receiving PDGF-AA ligands from the surrounding muscle cells (Ieronimakis et al., 2016). The gene discussed is PTPRC; the disease is Duchenne muscular dystrophy.