Atopic dermatitis (AD) is the most common pruritic inflammatory skin disease characterized by thickening of epidermis and dermis as well as by the infiltration of multiple pathogenic polarized T lymphocytes, including Th2, Th17, and Th22 cells. Significant progress has been made to develop targeted therapeutics for treating AD, e.g., Food and Drug Administration-approved dupilumab, an antibody for dual targeting of IL-4 and IL-13 signaling pathways. Additionally, a growing body of published evidence and a promising result from the early stage of the clinical trial with ILV-094, an anti-IL-22 antibody, strongly support the notion that IL-22 is a potential therapeutic target for treating AD. Moreover, we also experimentally proved that IL-22 contributes to the pathophysiology of AD by employing a murine model of AD induced by epicutaneous sensitization. Here, we review recent preclinical and clinical findings that have advanced our understanding of the roles of IL-22 and Th22 cells in skin inflammation. We conclude that blockade of IL-22 signaling may be a promising therapeutic approach for the treatment of AD.
Keywords: Atopic dermatitis; IL-22; Th22.