Figure 1.

Skin regulatory T (Treg) cell trafficking and maintenance. (a) An abrupt wave of Treg cells accumulate in skin early in neonatal life. Commensal microbe elicitation of the chemokine CCL20 from hair follicle epithelial cells attracts CCR6‐expressing Treg cells to preferentially migrate to skin during this defined window of postnatal tissue development. (b) Treg cells in skin are maintained and/or induced by interactions with both epidermal Langerhans cells (LCs) and CD141⁺ dermal dendritic cells (DDCs). Skin‐homing Treg cells are defined by expression of CCR4, CD103, cutaneous lymphocyte antigen (CLA), and FuT7. ‘(M)’ or ‘(H)’ denotes pathways that have been identified in mouse or human, respectively.