Reply to Slominski et al.: UVB irradiation induces proenkephalin+ regulatory T cells with a wound-healing function

Foxp3+CD25+CD4+ regulatory T (Treg) cells constitute about 10% of peripheral CD4+ T cells and suppress a variety of immune responses in mice and humans (1). Our recent report (2) shows that proenkephalin (PENK)-expressing Treg cells expanded by ultraviolet B (UVB) exposure promoted wound healing. The Letter from Slominski et al. (3) points out that skin-resident cells produce enkephalins and other neuropeptides and that skin neuroendocrine activity exerted by keratinocytes, fibroblasts, and melanocytes was detected early after UVB irradiation within a day (3⇓⇓–6), although they did not address possible roles of PENK produced by skin T cells (3⇓⇓– … [↵][1]2To whom correspondence may be addressed. Email: yamazas{at}med.nagoya-cu.ac.jp. [1]: #xref-corresp-1-1