Researchers in Japan have reported a promising advance in hair-regeneration research after identifying a previously unknown “third cell” that appears to be essential for fully regenerating hair follicles. The study was led by Riken together with Tokyo-based startup OrganTech, and it offers new insight into how future treatments for hair loss may go beyond slowing hair thinning and instead focus on rebuilding functioning follicles.
Hair follicles naturally move through a cycle of growth, transition, rest, and shedding. Although scientists had previously been able to create early hair follicle structures in laboratory settings using two known cell types — epithelial stem cells and dermal papilla cells — they had not been able to reproduce the complete cycle of growth, shedding, and regrowth outside a living body.
In this new study, the researchers identified around-bulge mesenchyme (ABM) cells as the missing third component. When these cells were combined with the two already known follicle cell types and transplanted into engineered skin, the team was able to reproduce the full hair-growth cycle in mice, including repeated growth and replacement.
The researchers found that ABM cells play a key role in helping follicles move from the resting phase back into the active growth phase, while also supporting proper follicle elongation. The study also provided a better understanding of how follicles physically develop, showing that the base of the follicle shifts downward into deeper skin layers as the hair shaft grows upward.
This discovery is important because most current treatments for alopecia and hair thinning mainly aim to slow hair loss rather than regenerate new follicles. While the research is still at an early stage and has only been demonstrated in mice, it represents an encouraging step toward future regenerative therapies that could one day offer more complete solutions for hair restoration.
Read the full article here https://www.japantimes.co.jp/news/2026/02/26/japan/science-health/hair-follicles-cells/