Lu Q. Le, MD, PhD
A surprising discovery from the University of Virginia School of Medicine is transforming our understanding of hair growth and could set the stage for new approaches to cure baldness.
Researchers led by UVA’s Lu Q. Le, MD, PhD, have discovered that a previously under-appreciated stem cell population in the upper and middle sections of the hair follicle is essential for hair growth. When these cells are depleted, hair growth stops. That suggests that replenishing or activating these stem cells could restore hair growth, the researchers report.
These malleable stem cells in the upper- and mid- hair follicle region are early ancestors of our hair, Le’s team found. That upends the long-accepted belief that hair growth begins with stem cells in an area near the bulbous base of the follicle technically known as “the bulge.”
“These findings add new foundational knowledge to hair follicle biology, showing, for the first time, that the bulge cells actually arise from this novel stem cell population,” said Le, chair of the Department of Dermatology at the UVA School of Medicine and UVA Health. “It is our hope that these stem cells could one day provide a novel therapy for treating hair loss in people.”
Understanding Hair Growth – and Loss
Each of the millions of hairs on our bodies grows from an individual follicle, like a tulip grows from a bulb. Le’s research casts new light on how these follicles form. The bulge above the bottom of the follicle, Le found, develops from stem cells located closer to the surface of our skin.
The stem cells – cells that can turn into other types of cells -– continue to play an essential role in hair growth after the follicle is established, the researchers discovered. Positioned along the hair shaft beneath the surface of the skin, the stem cells move downward to nourish and resupply the bulge at the follicle’s base. These cells serve as the earliest raw material for hair formation, Le and his collaborators believe.
In their lab tests, the researchers found that depleting these stem cells at certain times halted hair growth. That speaks to their essential role in hair formation and to their potential role in hair loss.
Based on their findings, Le and his team believe that keeping the stem cells active to ensure the follicle has adequate supply for hair growth could, with further research, offer a new way to combat hair loss. They are continuing their investigation but excited by the possibilities.
“We plan to fully investigate the potential of these stem cells in human hair follicles,” Le said. “Importantly, we found that in human bald scalp, although the hair shafts are gone, this population of novel hair stem cells is still present in the upper hair follicle. This means that if we could reactivate these cells to migrate down and repopulate the bulge, they could potentially regrow hair in bald scalp.”
Findings Published
The findings have been published as a cover story in the Journal of Clinical Investigation. The research team consisted of Elnaz Ghotbi, Edem Tchegnon, Zhiguo Chen, Stephen Li, Tracey Shipman, Yong Wang, Jenny Raman, Yumeng Zhang, Renee M. McKay, Chung-Ping Liao and Lu Q. Le. The researchers have no financial interest in the work.
The research was funded by the National Institutes of Health, grants R01CA166593 and R01EY033344.
Filed Under: Research