Bulge Progenitor Cells: A Promising Frontier in Hair Follicle Regeneration and Clinical Translation.

• Bulge progenitors' cells (BPC) are multipotent cells that fuel hair follicle cycling, sebaceous turnover, and epidermal repair.• BPC activation from quiescence is governed by niche-derived Wnt/β-catenin (anagen entry), BMP antagonism (licensing transit), and TGF-β/Smad (catagen enforcement).• Preclinical models demonstrate de novo folliculogenesis using BPC- dermal papilla cell recombinants in 3D scaffolds, with > 70% graft viability and restored cyclic hair growth.• Early-phase clinical trials of autologous BPC-enriched micrografts report 20-30% increases in hair density in androgenetic alopecia, with minimal adverse events.• Translational realization demands GMP-compliant isolation, biomimetic niche engineering (hydrogels, bioprinting), and immunomodulatory strategies to ensure safety, scalability, and durability.