Calcium-Mediated Electrical Communication in Epithelial Cells

For a long time, it was believed that only nerve and heart cells utilized electrical impulses for communication, while epithelial cells which form the linings of human skin, organs, and body cavities were considered silent, primarily acting as protective barriers that absorb and secrete various substances.

However, two researchers from the University of Massachusetts Amherst have challenged this conventional view by demonstrating that epithelial cells do indeed “talk” to each other, albeit through slow electrical signals.

Led by Steve Granick, Robert K. Barrett Professor of Polymer Science and Engineering, along with Postdoctoral Fellow Sun-Min Yu, their findings, recently published in the Proceedings of the National Academy of Sciences, could pave the way for new applications ranging from wearable bioelectric sensors to enhanced wound healing.

Granick and Yu utilized a chip coated with epithelial cells, equipped with 60 precisely arranged electrodes capable of detecting minute electrical changes.

Epithelial cells do things that no one has ever thought to look for. When injured, they ‘scream’ to their neighbors, slowly, persistently, and over surprising distances. It is like a nerve’s impulse, but 1,000 times slower.”

Steve Granick, Robert K. Barrett Professor, University of Massachusetts Amherst

Their curiosity-driven research, which integrates polymer science and biology, revealed this previously unnoticed cellular signaling.

By employing a precise laser to create “sting” patterns on individual cells, they observed how signals propagated outward.

Sun-Min Yu explained, “We tracked how cells coordinated their response. It is a slow-motion, excited conversation.”

In contrast to the rapid neurotransmitter releases seen in nerve cells, epithelial cells depend on ion flows particularly calcium to generate signals that, while significantly slower than those in nerve cells, exhibit similar voltages. These signals can persist for extended periods: Granick and Yu noted that cells were able to “talk” for over five hours across distances nearly 40 times their length.

While Granick and Yu established that calcium ions are essential for this epithelial communication, they have yet to explore other potential contributors to this signaling process. Although the immediate applications of their discovery are still unfolding, the implications are extensive.

“Wearable sensors, implantable devices, and faster wound healing could grow from this,” Granick noted.

“Understanding these screams between wounded cells opens doors we did not know existed,” Yu added.