Hair Follicle Stem Cells Repair Wounds by Converting Effector T Cells into Regulatory T Cells to Shield Against Inflammation

Hair follicle stem cells (HFSCs) play a crucial role in wound repair by converting effector T cells into regulatory T cells (Treg cells) to protect against inflammation. This study used lineage tracing, RNA sequencing, and microscope imaging to observe HFSCs during wound healing and found that these cells express CD80, an immunomodulatory ligand. The presence of CD80 is essential for effective wound healing, as its absence impairs the process. CD80-expressing HFSCs do not increase Treg cells through differentiation or proliferation but instead induce Foxp3 expression in effector T cells, converting them into Treg cells. This mechanism helps build a protective barrier, facilitating wound repair.