The superficial aspects of regenerative medicine and attempts to revert portions of the aging process attract far more attention than the meaningful aspects. People seem much more interested in evading baldness and making skin look good than in restoring youthful function to the inner organs whose failure will kill them. You can live with baldness, and not with a age-damaged heart, but you wouldn't know that if going just by the level of discussion devoted to these topics. This is far from the only area of life in which observed priorities fail to match up to the best course for personal self-interest, of course.
The ultimate victory, when it comes to the long-fought battle against baldness, would be to find a way to trick the body into creating brand-new hair follicles. Researchers first raised the possibility in the 1950s, when they observed new hair follicles forming during wound healing in rabbits and mice, but the work was later discredited. Then, in 2007, George Cotsarelis, a dermatologist at the University of Pennsylvania's Perelman School of Medicine, spotted hairs growing in the middle of small cuts they'd made in the skin of adult mice. "We figured out they were de novo hair follicles formed in a process that looked a lot like embryogenesis," says Cotsarelis.
It turns out that the wound-healing process causes skin cells to dedifferentiate, providing a limited time window during which those cells can be persuaded to form new hair follicles. Even more intriguingly, the researchers also found that inhibiting Wnt signaling during this window reduced follicle neogenesis, while overexpressing Wnt molecules in the skin increased the number of new follicles. In 2006, Cotsarelis, Zohar, Steinberg, Olle, and several other scientists cofounded a company called Follica to develop new combination therapies to induce follicle neogenesis. Although Follica has released few details on their proprietary procedure, the general idea is clear: their patented minimally invasive "skin perturbation" device removes the top layers of skin, causing the underlying skin cells to revert to a stem-like state, after which a molecule is applied topically to direct the formation of new hair follicles.
Indeed, Follica has already done preclinical and clinical trials, says Olle, "all of which confirm that we can consistently create new hair follicles in mice and in humans. As far as I know, no other approach has been able to achieve that." News of the progress has attracted strong interest from the public, with comments piling up below online articles about Follica and serving as de facto message boards for the science-savvy bald community to exchange expressions of hope and skepticism - and to speculate about when the "cure" might hit the market. Earlier this year, Cotsarelis's group sparked another comment frenzy by demonstrating that a protein called fibroblast growth factor 9 (Fgf9), which is secreted by gamma delta (γδ) T cells in the dermis, plays a key role in the formation of new follicles during wound healing in adult mice.