Cure For Baldness? Scientists Grow Hair Follicles On Mice

Its more than a sign of aging, it can also be annoying and embarrassing. Going bald affects both men and women as they grow older. In fact, the American Hair Loss Association says two-thirds of American men will experience “notable” hair loss by age 35. This number increases to an overwhelming majority of 85% once men hit 50. Women aren´t safe either, making up 40% of the entire balding population. Now, as scientists try to reverse or completely rectify the situation, a team in Tokyo, Japan has made a new advancement.

A new study shows bioengineered hair follicles can become actual hair when transplanted into normally hairless mice. Such an advancement could lead to not only better hair transplants, but also fewer cases of baldness.

The engineered hair follicles were patched into the skin and, once there, managed to connect to surrounding tissue in order to grow hair in an organized way. Current hair transplant methods simply move follicles from one area of the body to the other. This new approach encourages new hair follicles to grow from existing cells. More than just covering up an unsightly bald spot, study coauthor Takashi Tsuji of Tokyo University of Science in Chiba, Japan says the new study also marks an advancement in organ regeneration, such as salivary glands which form in much the same way as hair follicles.

Tsuji and his colleagues detail their findings in the April 17th issue of Nature Communications.

Hair follicles are formed when epithelial cells and mesenchymal cells interact and respond with one another. As they work in tandem, the epithelial cells grow and regenerate very quickly while the mesenchymal cells tell the epithelials to make a follicle.

Tsuji and his team have engineered follicles and hair shafts from mouse embryos before. This new study marks the first time these follicles were able to organize into clusters and grow normal hair when inserted into a mouse´s skin.

The Japanese team used acetylcholine, a drug used to cause muscles to contract, to inject a region of skin with the bioengineered follicles. As they did this, the hairs began to perk up, suggesting the transplanted follicles had integrated with surrounding muscles and nerves, just like regular hair follicles.

To ensure the hairs grew in the right direction and to avoid ingrown hairs, the team used nylon string to encourage the hairs to grow up and out.

“You have to make hair that is positioned right,” Cheng-Ming Chuong, a stem cell and regeneration researcher at the University of Southern California in Los Angeles, told Rebecca Cheung of Science News Magazine.

Chuong notes one of the ways the study succeeded was in getting the follicles to grow in an organized manner, unlike prior studies, which were unable to do so. When these follicles grow without organization, cysts can form, making them of little use in clinical tests.

Tsuji and his team were also able to create functional follicles from regular adult mice. In growing the two types of hair together, the team engineered follicles capable of growing finer, whisker type hair.

Now, the team looks to human cells. By using similar methods, the team will gather cells from men with male pattern baldness and create individual follicles like the ones that grew on the mice.