Screaming Skin

Skin cells call out for help when injured

- Allison Parshall

NEURONS TALK to one another using electricity. If you could hear these impulses, they might sound like constant, rapid-fire chatter all over the nervous system. Heart muscle cells do something similar, issuing electrical "heave-ho" signals that make the organ beat.

Skin and other epithelial cells, however, were thought to be silent; they form barrier tissues that protect the body's interior from the outside world, and they weren't assumed to need this kind of communication. So researchers were amazed to discover recently that, when wounded, these cells emit a slow electric pulse in a way that resembles neuron firing.

"The epithelial cells are making a signal kind of like a scream: 'We got injured, we need repair, you need to come over here,"" says Sun-Min Yu, an engineer at the University of Massachusetts Amherst and lead author of the study, published in the Proceedings of the National Academy of Sciences USA. The signal may summon other cells to help rebuild the damaged spots.