Heart cell monitoring patch
A system for growing heart cells on a 3D electrically-conductive meshwork to study their behaviour has been developed by US researchers.
The heart is an electrical organ. Each of the muscle cells or cardiomyocytes that form the heart are wired together so that signals controlling the heartbeat can propagate in an orderly fashion through the organ so that blood is pumped efficiently.
This structure makes the heart inherently hard to study and monitor though, because the cells are operating in a 3D architecture, which cannot be readily recapitulated in a dish.
Now Charles Lieber and his colleagues at Harvard in the US, writing in Nature Nanotechnology, have developed a silicon-based electrically-conductive mesh resembling microscopic chickenwire.
This can support the growth of cardiac cells in three dimensions and also be folded into a range of relevant shapes.
Even more useful is that, just as a touch-sensitive screen can decode where a finger is on its surface, the Harvard team's silicon mesh knows the physical addresses of each of the heart cells sitting on its surface, so the electrical signals issuing from individual cardiomyocytes can be recorded simultaneously.
This makes it possible to trace how an electrical signal spreads through a group of cells in real time, meaning that cardiac drugs can tested reproducibly and safely and models of heart disease such as genetic conditions that cause irregular heart rhythms can be investigated.
It should even be possible to mock-up an individual's heart by growing cardiomyocytes from their stem cells and using the model to optimise drug therapy in that person.
The electrically conductive nature of the meshwork means that it can also be used to deliver signals to the heart cells, working like a pacemaker.
Long-term this is important because Lieber and his team have their eye on using the approach to develop the cardiac equivalent of a "patch" that could be applied to a damaged region of the heart and then monitored electrically, or stimulated to control the beating of the adjacent native heart tissue...