Injectable and biofunctionalized fibrin hydrogels co-embedded with stem cells induce hair follicle genesis.

Fibrin-based hydrogels have been widely used in various tissue engineering because of their biocompatibility, biodegradability, tunable mechanical characteristics and nanofibrous structural properties. However, their ability to support stem cells for hair follicle neogenesis is unclear. In this study, we investigated the effect of fibrin hydrogels in supporting skin-derived precursors (SKPs) in hair follicle neogenesis. Our results showed that SKPs in fibrin hydrogels with high cell viability and proliferation, the stemness of SKPs could be maintained, and the expression of hair induction signature genes such as akp2 and nestin was enhanced. Moreover, hair follicle reconstruction experiments showed de novo hair genesis in mice and the hairs persisted for a long time without teratoma formation. More importantly, the blood vessels and sebaceous glands were also regenerated. Our study demonstrated that fibrin hydrogels are promising in hair follicle regeneration and have potential application in clinical settings for alopecia and wound healing.