Identification of stem cells vital for hair regeneration

A new method for restoring hair growth, which uses stem cells, has been developed. 

The method, developed by a team of researchers at the RIKEN Centre for Biosystems Dynamics Research in Japan, used stem cells to create hair follicles that can regrow hair after it falls out.

'Our culture system establishes a method for cyclical regeneration of hair follicles from hair follicle stem cells,' said Dr Takashi Tsuji, the lead author of the study, 'and will help make hair follicle regeneration therapy a reality in the near future.' 

Human hair growth follows a continuous process in which hair grows, falls out and then grows back again. When this cyclical process is impaired by hereditary genetics, severe stress or underlying health conditions, hair growth diminishes and eventually ceases, resulting in baldness or thinning hair. 

In the study, published in Nature Scientific Reports, researchers took fur and whisker cells from mice and cultured them in the lab with other biological 'ingredients'. They identified one type of collagen that, when combined with five additional factors, increased the number of cycles of normal hair production hair follicles went through.

When one of these ingredients was missing, hair follicles showed much less efficient cycling. Additionally, the Japanese team showed that the presence of a specific marker on the surface of the cells, named Itgβ5, was extremely beneficial to natural hair cycling, making it an essential component of the stem cell-based therapy.

'We found almost 80 percent of follicles reached three hair cycles when Itgβ5 was also bioengineered into the hair follicle germ,' explained Dr Makoto Takeo, first author of the study. 'In contrast, only 13 percent reached three cycles when it was not present.'

Dr Tsuji's team has been working on hair follicle regeneration for over ten years and preclinical animal studies were completed in 2019. The hair follicle regeneration treatment is now ready to enter human clinical trials.