An Extended Epidermal Response Heals Cutaneous Wounds in the Absence of a Hair Follicle Stem Cell Contribution

The study found that cutaneous wounds could heal effectively without hair follicle (HF) stem cells by using Edaradd mutant mice, which lack HFs. Although the absence of HF-derived cells caused an initial delay in wound reepithelialization, the wounds eventually healed completely due to an extended activation of the interfollicular epidermis (IFE). This extended epidermal response, marked by increased expression of keratin 6 (K6) and proliferating cell nuclear antigen (PCNA), compensated for the lack of HF stem cells. The findings challenged the belief that HF stem cells were essential for skin repair, demonstrating that IFE stem cells alone could facilitate wound healing.