Getty Images

Turning hair growth on its head — by transplanting hair follicles upside down — may provide hope for receding hairlines.

It’s one of the more vexing problems in medicine — about half of men and women over age 50 experience hair loss, from thinning of their scalp to male pattern baldness. Their options, however, are few. Medications can only slow the rate of loss, without generating lush new growth, while surgical strategies essentially move hair-growing cells from one part of the scalp to another, with varying success.

The ideal solution would be one that prompts defective hair follicles to sprout new hair, or that allows transplanted follicles to have a greater chance of laying down roots. And in new research published in the journal Proceedings of the National Academy of Sciences, scientists led by a team at Columbia University Medical Center reveal one potentially robust way of accomplishing this feat.

Working from the knowledge that hair follicles may need just the right cellular and molecular environment to do their job, the scientists transplanted not just the hair follicles, which serve as the root for new hair growth, but the dermal papilla cells that accompany them. The key was to transplant them in a three-dimensional sphere of cells — and upside down — so that all of the cells could communicate and interact with one another to send the right signals to prompt hair growth. To test the strategy, the researchers grew dermal papilla cells from seven human donors and cloned the cells in tissue culture. After several days, they transplanted the cultured papillae between the dermis and epidermis layers of human-skin samples. The human skin was then grafted onto the back of mice. Five of the seven transplants led to hirsute patches that lasted for at least six weeks.

The hairs were still small, but the researchers are encouraged because they used human skin that normally is completely hairless — the foreskins from circumcised babies. Essentially, they generated hair growth in cells that normally have no capacity for sprouting hair.

“This suggested that if we cultured human papillae in such a way as to encourage them to aggregate … it could create the conditions needed to induce hair growth in human skin,” study author Claire A. Higgins, an associate research scientist said in a statement about the research.

If the results are validated, the scientists anticipate that the technique could be used to treat everything from male pattern baldness to female hair loss and burn patients who have lost the upper layers of skin that contain hair follicles.