NOTCH3 and atherosclerosis: Notch3 was recently suggested to regulate clonal proliferation of smooth muscle cells in pulmonary arteries,52 whereas Notch1 (but not Notch3) mutants affected neointima formation in carotid arteries.53 VSMC proliferation was associated with cell death in both arterial injury and in the atherosclerosis model, similar to what has been suggested.54,55 It is therefore tempting to speculate that cells forming Path2 in the scRNA-seq analysis constitute dying cells.