A role for skin gammadelta T cells in wound repair.

Gammadelta T cell receptor-bearing dendritic epidermal T cells (DETCs) found in murine skin recognize antigen expressed by damaged or stressed keratinocytes. Activated DETCs produce keratinocyte growth factors (KGFs) and chemokines, raising the possibility that DETCs play a role in tissue repair. We performed wound healing studies and found defects in keratinocyte proliferation and tissue reepithelialization in the absence of wild-type DETCs. In vitro skin organ culture studies demonstrated that adding DETCs or recombinant KGF restored normal wound healing in gammadelta DETC-deficient skin. We propose that DETCs recognize antigen expressed by injured keratinocytes and produce factors that directly affect wound repair.