Scientists Find The Silent ‘Scream’ of Human Skin For The First Time

US Researchers have discovered that epithelial cells that line human skin and organs are able to communicate danger to the body through a silent ‘scream’, instead of communicating through neurons like the rest of the body.

Indeed, this is true for the rest of the body, as the nervous system uses neurons, which are essentially bioelectrical signals, to trigger the appropriate response for the rest of the body.

The ‘silent’ scream find has come as a surprise, as the cells had been previously considered mute. This discovery may also open the possibility for electrical medical devices to accelerate the healing process.

The human skin’s silent ‘scream’ is like a nerve impulse but 1,000 times slower

Polymath Steve Garnick of the University of Massachusetts Amherst said “Epithelial cells do things that no one has ever thought to look for,” explaining that, “When injured, they ‘scream’ to their neighbors, slowly, persistently, and over surprising distances. It’s like a nerve’s impulse, but 1,000 times slower.”

Researchers Steve Garnick, biomedical engineer Sun-Min Yu,and Robert K. Barrett led the experiment that designed a system to investigate how cells communicate in the epithelium, which consists of a chip connected to 60 electrodes.

The Chip was covered with a single layer of lab-grown human keratinocytes which are the primary cells that form the outer layer of the human skin. They then used a laser to simulate an injury on the artificial skin and were able to observe the wounded skin cells producing electric signals similar to the ones produced by neurons at a slower pace.

Yu said that during the experiment, they tracked how cells coordinated their response to injury, describing it as “a slow-motion, excited conversation.”

The experiment shows skin cells send signals at speeds of around 10 millimeters per second

The research team was able to determine some of the speeds at which skin cells communicate with the rest of the body, as well as the remarkable distances they travel, which are hundreds of micrometers from the wounded area.

Additionally, the researchers noted that the communication heavily relied on ion channels, which are small pores found in cell membranes that transport charged ions in the body. The researchers also noted that the signals produced by the epithelial last longer than neuron signals, with some of the signals having a duration of up to five hours.

Despite these differences, however, the research team highlighted some similarities with neuron signals, as the voltage of the signals was of similar amplitude, and the epithelial ‘communication’ went through phases, similarly to neuronal communication.

It is also worth noting that given the recency of this finding, more work is expected to be conducted to fully understand how the silent ‘scream’ works, specifically what the cells are using for the signal.