Wounded Skin Heals Quicker the Second Time Around


We live in a world where we are always exposed to harmful elements including irritants, pathogens, and ultraviolet radiation. That statement was made by an immunologist, Shruti Naik. He posted the question, “do these stressors have any kind of lasting impact on cells?”

It was believed that our immune system is known to remember inflammatory events and infections so that they can respond much quicker the next time. If that is true for immune cells, would that also be true for epithelial stem cells as well?

The Study

Naik’s curiosity led her to create a study. Naik and her team got a sample of mice and they induced inflammation in them by exposing the said animals’ skin to fungal infection, mechanical wounding, and certain chemicals.

They then measured how long it would take for the skin to heal after inducing the same injury on the same site for a second time. They took the average and they find that no matter what type of injury it is; the same area’s skin would heal about 2.5x quicker than the skin of the mice that were injured just the first time.

To help uncover this mystery, Naik and her team searched for genetic markers in the epithelial stem cells that maintained its chromosomal accessibility even after the first injury.

They found that multiple regions of chromatin were left as is for up to 180 days after an injury occurred, which leave the pathway open, making certain repairs much faster in light of a second injury. In other words, the transcription of response genes is far more effective in handling an injury response whenever the same site was damaged due to injury the second time around.

George Cotsarelis, a dermatologist at the University of Pennsylvania’s Perelman School of Medicine, said that Epithelial stem cells are the first cells of nonimmune variety to have this kind of memory in response to injuries.

Current findings suggest that it is actually a primitive response that was made to enhance the different cells in the body to make the necessary changes and to make the healing process quicker the second time around.

In conclusion, the next time you get injured at the same spot, expect that you get healed much quicker.