Despite intensive research, the pivotal factors that link abnormalities in permeability of the dermal barrier with inflammation and the generation of skin lesions in allergic dermatitis (AD) remain unknown. In a landmark paper published by Jin et al in the Journal of Clinical Investigation, IL-21 is identified as a critical regulator of the processes that lead to sensitization and allergic inflammation of the skin. Although mouse models do not reflect all of the complexities of human disease, the data presented by Jin et al are important first steps in identifying a new pathway that may have potential therapeutic implications for the treatment of AD. Future studies will require confirmation of the up-regulation of IL-21/IL-21R signalling system in extended populations of AD patients and the subsequent development of topical anti-IL-21 treatments.
Immunology and Cell Biology Vol. 87, Issue 5, p. 359-360