Ultraviolet B exposure expands proenkephalin+ regulatory T cells with a healing function

(Nagoya City University) Skin exposure to ultraviolet B (UVB) induces expansion of regulatory T (Treg) cells with immunosuppressive activity. Here researchers found that UVB-expanded skin Treg (UVB-skin Treg) cells had a tissue repair function. UVB-skin Treg cells expressed proenkephalin (PENK) and amphiregulin (AREG), which promoted keratinocyte outgrowth and skin wound healing. Their results provide a new implication in developing a therapy using UVB-skin Treg cells.