Autografted hair follicles with dermal papilla removed promote wound repair and regeneration in Bama mini-pigs

Autologous free flap transplantation is the most economical and effective method for clinical treatment of large-area trauma, but the shortage of flap donors prevents widespread use of this method. Hair follicle stem cells have great potential to repair wounds, but wound repair by hair follicle stem cells has not yet met expectations. We used a wound model of Bama mini-pigs and treated the wound with autologous hair follicles or flaps. The wound healing was observed on days 7, 14, and 21 post-surgery and wound healing rates were analyzed using Image J software. Hematoxylin and eosin staining was performed to evaluate re-epithelialization of the wound. Immunofluorescence staining was used to detect the expression of hair follicle stem cell markers (CK15, Sox9) and explore the mechanism of wound repair. This research found that autologous hair follicles can accelerate wound healing. The efficiency of hair follicles in wound repair is related to their structure. Dermal papilla acts as a biological barrier to hair follicle-mediated wound repair. Dermal papilla removal enhances wound healing efficiency, likely by relieving dermal papilla-imposed restrictions on hair follicle stem cell migration. Autologous hair follicles for wound repair has the advantages of minimal damage, simple fabrication, and abundant source, which may be able to replace the flap transplantation as a therapeutic strategy in the future. This study is helpful to elucidate the regulatory mechanism of hair follicles involved in wound repair, and has important academic and clinical value for solving the problem of shortage flap donor.