Rescuing Key Native Traits in Cultured Dermal Papilla Cells for Human Hair Regeneration

The study demonstrated that preconditioning human dermal papilla (DP) cells with keratinocyte-conditioned medium (KCs-CM) significantly enhanced their hair-inductive properties, crucial for hair regeneration. Key findings included increased alkaline phosphatase (ALP) activity, reduced expression of α-SMA and versican V1, and improved self-aggregation capacity. KCs-CM also modulated the secretion of hair growth mediators like VEGF and IL-6 while decreasing BMP2 and TGF-β1 levels. In vivo, co-grafting KCs-CM preconditioned DP cells with keratinocytes in mice led to the formation of hair follicle (HF) and sebaceous gland (SG)-like structures in 5 out of 7 animals. This approach showed promise for human hair regeneration, representing the best results achieved with adult human cells to date.