Development and functional specialization of CD103+ dendritic cells

Abstract

Summary: CD103 (α_E) integrin expression distinguishes a population of dendritic cells (DCs) that can be found in many if not all lymphoid and non‐lymphoid organs. CD103⁺ DCs display distinct functional activities. Migratory CD103⁺ DCs derived from skin, lung, and intestine efficiently present exogenous antigens in their corresponding draining lymph nodes to specific CD8⁺ T cells through a mechanism known as cross‐presentation. On the T cells they prime, intestinal CD103⁺ DCs can drive the induction of the chemokine receptor CCR9 and α₄β₇ integrin, both known as gut‐homing receptors. CD103⁺ DCs also contribute to control inflammatory responses and intestinal homeostasis by fostering the conversion of naive T cells into induced Foxp3⁺ regulatory T cells, a mechanism that relies on transforming growth factor‐β and retinoic acid signaling. This review discusses recent findings that identify murine CD103⁺ DCs as important regulators of the immune response.