Scientists have developed organ chips that mimic heart disease

When studying disease or testing for potential drug therapies, researchers typically rely on cells in petri dishes or experiments with laboratory animals, but recently scientists have developed a different approach: to model human organ functions and to act as Organ chip smaller devices that are cheaper and more efficient tools.

Now, researchers have created a new device that is particularly well suited for establishing models of atherosclerosis, the leading cause of heart disease and stroke, published in a January 2 issue of the American Physical Federation Publishing Group In the paper Applied Physics Letters - Bioengineering, the researchers showed how the new device can be used to study the important inflammatory reactions that occur in vascular cells, which can not be done using animal models.

'Atherosclerosis is a very important and complex disease,' says Han Wei Hou, a biomedical engineer at Nanyang Technological University in Singapore, when fat, cholesterol and other substances in the blood form plaques that accumulate on the lining of the artery wall , This disease will appear.

Understanding what is important in regulating this abnormal vasoconstriction is important for researching and treating vascular disease and for preventing acute myocardial infarction, Hou said that when researchers developed organ-chip models for the blood vessels earlier, they focused more on Recreate the biological complexity of blood vessels rather than their shape and geometry - the key to atherosclerosis. 'The disease involves not only the biological aspects of endothelial dysfunction but also the biomechanics of blood flow.'

To do this, the researchers created a device mounted on a 1-inch-square chip that contains two stacked chambers separated by a thin, flexible polymer film that contains air at the top and mechanical properties at the top Researchers flowed endothelial cells lining the blood vessel inside a fluid-filled chamber above the membrane, and then they pumped air into the bottom chamber so that the chamber would stretch like a balloon and form a fluid barrier that would stop the fluid Flowing bubbles. This process mimics vasoconstriction.

The fluid-filled chambers contract, causing the fluid to flow faster in some areas and slower in others. As the researchers grow cells under constant but slow fluid flow conditions, endothelial cells can grow and express A protein called ICAM-1, which is associated with inflammation and plays an important role in the development of atherosclerosis.

The researchers found that when human blood was used instead of cell culture media, more of the immune cells called monocytes bound to endothelial cells at low flow rates, monocytes were the leading cause of lipid accumulation, and lipids Accumulation eventually develops into atherosclerotic plaques.