Engineered endothelium model enables recapitulation of vascular function and early atherosclerosis development

Human health relies heavily on the vascular endothelium. Here, we propose a novel engineered endothelium model (EEM), which recapitulated both normal vascular function and pathology. An artificial basement membrane (aBM), where porous polyvinyl alcohol hydrogel was securely integrated with human fibroblast-derived, decellularized extracellular matrix on both sides was fabricated first and followed by endothelial cells (ECs) and pericytes (PCs) adhesion, respectively. Our EEM formed robust adherens junction (VE-cad) and built an impermeable barrier with time, along with the nitric oxide (NO) secretion. In our EEM, ECs and PCs interacted each other via aBM and led to hemoglobin alpha 1 (Hb-α1) development, which was involved in NO control and was strongly interconnected with VE-cad as well. A resilient property of EEM under inflammatory milieu was also confirmed by VE-cad and barrier recovery with time. In particular interest, foam cells formation, a hallmark of atherosclerotic initiation was successfully recapitulated in our EEM, where a series of sequential events were confirmed: human monocytes adhesion, transendothelial migration, and oxidized low-density lipoprotein uptake by macrophages. Collectively, our EEM is excellent in recapitulating not only normal endothelium but early pathologic one, thereby enabling EEM to be a physiologically relevant model for vascular study and disease modeling.