Source: American Institute Of Physics
Summary: Researchers have built a new device that’s especially good for modeling atherosclerosis – the constriction of blood vessels that’s the leading cause of heart attacks and strokes.
Researchers usually turn to cultured cells on Petri dishes or experiments with lab animals to study diseases or test potential drug therapies. But recently they have been developing a different approach: small, organ-on-a-chip devices that mimic the functions of human organs, serving as potentially cheaper and more effective tools. Atherosclerosis is a very complex disease develops when fat, cholesterol and other substances in the blood form plaque that accumulates on the inside walls of arteries. This buildup constricts the blood vessel, causing cardiovascular diseases. Researchers from the American Institute Of Physics have built a novel tunable microfluidic atherosclerosis model to study vascular inflammation and leukocyte-endothelial interactions in 3D vessel stenosis and also explained how this organ-on-a-chip could improve blood testing for patients. The study findings were published in the journal APL Bioengineering.
The device fits on a single square-inch chip, consisting of two stacked chambers separated by a thin and flexible polymer membrane. The bottom contains air while the top contains a flowing fluid similar in mechanical properties to blood. Inside the fluid-filled chamber on top of the membrane, the researchers grow endothelial cells – the cells that line the inside of blood vessels. As a proof-of-concept experiment, the researchers pumped blood spiked with TNF-alpha, a protein that’s a sign of inflammation, into the device. The inflamed blood caused more immune cells to bind to the endothelial cells than normal. Measuring the number of bound immune cells can reveal the level of inflammation in the blood, an indicator of early atherosclerosis.
In contrast to other tests that just count the number of immune cells circulating in the blood, this technique could more accurately assess early immune responses in patients. This device could potentially help researchers better understand atherosclerosis and develop new treatments.
Biomedical engineer, Han Wei Hou said, “The new model can more accurately simulate atherosclerosis because [the] researcher can precisely tune constriction by controlling the air pressure,” and further added, “[The device] has a lot of promise in terms of diagnostics.”
More information: Nishanth Venugopal Menon et al, “A tunable microfluidic 3D stenosis model to study leukocyte-endothelial interactions in atherosclerosis, APL Bioengineering (2018). DOI: 10.1063/1.4993762