IL-17 producing cells in host defense and atopy

The roles of IL-17 producing cells have been the subject of significant research in the fields of autoimmunity, host defense, and recently, atopy. A substantial number of genetic disease with disruptions in the IL-17 pathway have been identified and characterized in past few years, not only enhancing our understanding, but also raising new and complex questions. The connection between IL-17 and atopic disease, in particular, is complex, but it merits further study which may ultimately lead to therapies targeting the Th17 pathway in infectious and/or allergic settings.

► Numerous genetic diseases affecting the IL-17 pathway have recently been identified, greatly enhancing our understanding of this pathway, while raising new questions.
► Evidence for the role of IL-17 in the pathogenesis of atopic disease is complex, with some studies suggesting a pathogenic role, and others a protective one.
► Roles for IL-17 in the induction of disease versus exacerbation may be different.