Researchers at Washington State University have identified a genetic factor that allows adult skin to repair itself like the skin of a newborn baby. The discovery has implications for better skin wound treatment as well as preventing some of the aging process in skin.
In a study, published in the journal eLife on September 29, the researchers identified a genetic factor named "Lef1" that acts like a molecular switch in the skin of baby mice that controls the formation of hair follicles as they develop during the first week of life. The switch is mostly turned off after skin forms and remains off in adult tissue. When it was activated in specialized cells in adult mice, their skin was able to heal wounds without scarring. The reformed skin even included fur and could make goosebumps, an ability that is lost in adult human scars.
In a report published on the university's website, Dr. Ryan Driskell, lead author and assistant professor in WSU's School of Molecular Biosciences, said: "We were able to take the innate ability of young, neonatal skin to regenerate and transfer that ability to old skin." Mammals are not known for their regenerative abilities compared to other organisms, such as salamanders that can regrow entire limbs and regenerate their skin.
"We can still look to other organisms for inspiration, but we can also learn about regeneration by looking at ourselves. We do generate new tissue, once in our life, as we are growing," he added.
Driskell's team used a new technique called single-cell RNA sequencing to compare genes and cells in developing and adult skin. In developing skin, they found a transcription factor -- proteins that bind to DNA and can influence whether genes are turned on or off.
The factor the researchers identified was associated with papillary fibroblasts which are developing cells in the papillary dermis, a layer of skin just below the surface that gives skin its tension and youthful appearance.
A lot of work still needs to be done before this latest discovery in mice can be applied to human skin, but this is a foundational advance.