Endothelial-to-mesenchymal transition (EndoMT) determined by double labelling with pan-endothelial marker, platelet endothelial cell adhesion molecule 1 (PECAM-1), αSMA, and Tie2-YFP lineage-traced cells in rodent models of kidney disease discovered that the EndoMT process contributed to ∼40% of all myofibroblasts (Zeisberg et al., 2008). Here, PECAM1 is linked to kidney disorder.