Atherosclerosis is hard to study due to the lack of an in vitro human arterial model. This research introduces a microfluidic endothelial cell – aendothelial cell (EC)–smooth muscle cell (SMC) 3D co-culture platform that can simulate the arterial wall cells both structurally and biologically. Various early atherogenic events were studied on chip by endothelial stimulation. They also showed the atheroprotective effects of drugs like Vitamin D and metformin on the wall on chip.