Hair Follicle Neogenesis Induced by Cultured Human Scalp Dermal Papilla Cells

In 2009, researchers successfully developed a method to expand human hair follicle dermal papilla (DP) cells in vitro, maintaining their hair-inductive potential for potential use in hair loss treatments. The expanded DP cells, after approximately 36 doublings, were able to consistently induce hair formation in an in vivo flap-graft model, and the induced hair follicles persisted and could regrow even 11 months post-grafting. Out of nine human DP cell cultures expanded for three passages, seven induced robust hair growth, one showed intermediate results, and one did not induce hair growth, with the inductive potential maintained through at least eight passages. The study confirmed that the cultured DP cells were responsible for hair induction as they formed the DP and connective tissue sheath of the follicles. This research marked a significant step towards developing new therapies for hair loss by demonstrating that cultured human DP cells can be used to induce hair growth.