Observing human heart muscle cells normally means opening someone’s chest, but no longer. Now they can be observed and studied outside the heart with a microscope, and scientists at the University of California Berkeley working with bio-engineers have for the first time developed a system that allows human heart cells to function outside the body.
“It is the first demonstration of an actual human heart which is based in a system that is mimicking the physiology as close as possible,” says post-doctoral fellow and researcher Anurag Mathur.
Californian scientists call the device a heart-on-a-chip. The system is comprised of cell layers derived from human adult stem cells, which can be converted into many different types of tissue. These cells are housed on a small slab of silicon. To keep the cells beating, micro-fluidic channels thinner than a human hair nurture the cells and also provide a way to deliver drugs to them for testing.
“These are mock blood vessels, similar to blood vessels. The fluid that we are interested in comes across this tissue and then it bathes it with the drug. We give it caffeine, the heart-on-a-chip beats and accelerates its heart rate. We give it adrenaline and it accelerates its heart rate,” says Professor of Bioengineering and Material Science Kevin Healy.
Scientists believe that by mimicking human physiology, the device could provide a new and powerful tool for drug development. Currently, pharmaceutical companies spend billions testing new drugs on animal models that more often than not fail in predicting if new drugs are toxic to humans. The heart chip could revolutionize drug screening by providing a tool that can be modified to model human diseases using human cells to test new drugs. The research is still in its infancy, but Healy says its potential is enormous.