Researchers at Berkeley have orchestrated the flow of cell groups by using electrical currents. It's a tissue engineering breakthrough that could eventually lead to "smart bandages" that use electricity to guide cells during the wound healing process.


The process is called galvanotaxis — the use of electricity to direct cell movement. Previous studies have shown that the method can work for individual cells, but this is the first example of galvanotaxis being used to direct "herds" of cells.

In this case, the researchers used single layers of epithelial cells, the same kind of cells that bind together to form robust sheaths in skin, kidneys, cornea, and other organs. By applying an electric current of about five volts per centimeter, the researchers encouraged the cells to migrate along the direct current electric field. In the gif above, cells can be seen performing a sudden u-turn after such an application.


Top image (a) shows a clump of epithelial cells. The white lines in (b) show the electric current flowing from positive to negative over the cells. In image (c), the cells can be seen tracking the electric field, with blue indicating leftward migration and red signaling rightward movement.

Amazingly, the researchers were also able to make the cells create elaborate shapes, such as a triceratops and the UC Berkeley Cal bear mascot.


More seriously, the breakthrough could result in powerful new tools used in tissue engineering. Rather than manipulating one cell at a time, researchers may be able to develop a few simple design rules that would provide a global cue to control clumps of cells.

Indeed, our bodies are full of flowing ions and salt solution. Electricity already plays a big role in our physiology, whether it be neural transmissions or muscle stimulation. The researchers are now trying to figure how how bioelectrical signals can facilitate the wound healing process.


It's widely known that an injury to the body creates a change in the electric field at the wound site. So, by mapping the changes in the electrical field when an injury occurs and it heals, it's hoped that this technique can be used to speed-up and improve this natural process. And in fact, it's this exact kind of cellular control that could be used to create a smart bandage.

Read the entire study at Nature Materials: "Galvanotactic control of collective cell migration in epithelial monolayers."


Images: Daniel Cohen