Endothelial cell culture model of carotid artery atherosclerosis.

Atherosclerotic lesions form non-randomly at locations in bends and bifurcations where the local flow can be classified as 'disturbed flow' and is associated with low shear stress oscillatory or reciprocating flow. Endothelial cells in vivo are constantly exposed to mechanical stimulation due to hemodynamic loading in the form of pulsatile pressure, cyclic stretch and shear stress to maintain phenotype and control function. In conditions like atherosclerosis, the pressure and strain loading remains the same whereas the local fluid flow behavior and shear stress are altered. Common in vitro models of atherosclerosis focus primarily on shear stress without accounting for pressure and strain loading. To overcome this limitation, we used our microfluidic Endothelial Cell Culture Model (ECCM) to achieve accurate replication of pressure, strain and shear stress waveforms associated with both normal flow seen in straight sections of arteries and disturbed flow seen atherosclerosis lesion susceptible regions. We specifically recreated mechanical stresses associated with the proximal internal carotid which is a major risk factor for stroke. Cells cultured using both conditions show distinct differences in alignment and cytoskeletal organization. In summary we recreated pressure, stretch and shear stress loading seen in straight sections and in the proximal internal carotid in a cell culture compatible platform.