Fully functional hair follicle organ regeneration using organ-inductive potential stem cells with an accessory mesenchymal cell population in an in vitro culture system

This study demonstrates the successful regeneration of fully functional hair follicles using organ-inductive potential stem cells combined with an accessory mesenchymal cell population in an in vitro culture system. Researchers identified a specific cell population, PDGFRα+/Sca1+/CD34+ mesenchymal cells, from the boundary zone of the epithelial stem cell niche, which plays a crucial role in promoting the hair cycle's downgrowth phase. By reconstituting hair follicle germs from bulge region-derived epithelial stem cells, dermal papillae, and mesenchymal cells, the study achieved full-size hair follicle regeneration and hair cycling both in vitro and after skin transplantation. This research advances the understanding of adult organ-inductive potential stem cells and their niches, contributing to the fields of basic and medical science related to organ morphogenesis and the adult hair cycle.