PECAM1 and metabolic dysfunction-associated steatotic liver disease: Consistent with the Hcfc1hepKO/Y male disease progression reflecting NAFLD, we observed (i) a progressive increase in the macrophage inflammatory marker F4/80 by 7 days (Fig. S7) and major clusters of F4/80-positive macrophages throughout at 18 days (Fig. 3D); (ii) extensive vascular endothelium development (i.e., CD31 or PECAM endothelial cell marker positive) (Fig. 3E); and (iii) both activated stellate cells (i.e., smooth muscle α-actin [SMA]-positive cells) (Fig. 3F) at 18 days and progressive increase in fibrosis (i.e., Sirius red positive) beginning around 9 days (Fig. 3G and Fig. S8).