Baldness breakthrough: Stem cells coaxed into growing hair
It could be the answer to the prayers of millions of men. Scientists have coaxed stem cells into growing hair for the first time.
At present, there are 7.4 million Britons affected by baldness. If they are unhappy about their appearance they are limited to choosing between a comb-over, a toupee or a transplant.
But within a decade, advances in stem cell science could help them to regrow their own hair where it has been lost.
The breakthrough could also lead to new treatments for other conditions, such as alopecia, in which hair is lost in patches.
Writing in the journal Nature, the scientists described how they had shown that adult mammals are able to grow new hair follicles.
It had been thought that follicles, the tiny structures responsible for hair growth, were always formed before birth, with their gradual death leading to baldness.
The discovery that it is possible to develop new follicles later in life paves the way for new hair loss treatments.
The University of Pennsylvania researchers made their discovery when studying the process of wound healing in mice.
They found that as the wound heals, new hair follicles form underneath the new skin ? allowing new hair to sprout.
Close examination showed that the follicles were formed from stem cells ? master cells capable of turning into different cells and tissues.
Key to the process was a protein called wnt, which is usually active only in the womb. If levels of the protein are increased, more hair grows. Without wnt, no hair grows.
Adding wnt also helped the wounds to heal better. It is thought that when the skin heals itself, it returns to a state similar to that found in the developing foetus, allowing new, fully functional follicles to form.
Although all work so far has been carried out in mice, the researchers are hopeful a similar technique could lead to treatments for humans.
Because wounding appears essential to the process, it is likely the skin would be grazed in the area to be treated, and a wnt-based drug given.
So far, all hair produced has been white, suggesting new hair would have to be dyed to make it look more natural. The first human trials are, however, at least two years away ? and any cure for baldness is not expected for a decade.
Experts have described the breakthrough as “remarkable”.
Dr Denis Headon, a developmental biologist from Manchester University, said: “Up to now we thought that the number of hair follicles we have is set before we were born and can only go downhill from there.
“This work shows that new hair follicles are made in adult skin, at least when it is healing a wound. The implication is that it might be simpler than we thought to make new hair follicles as a treatment for hair loss.”
Other remedies may appear on the market more quickly, with British scientists believing it may be possible to restore hair growth via a series of injections.
