Interleukin-17 and airway remodelling.

Interleukin (IL)-17A is emerging as important in reinforcing innate immunity by orchestrating sustained neutrophilic mobilisation. Even though there are indications of association with specific airway diseases, there is still no final proof that IL-17A plays a truly causative pathogenic role. There is evidence in mice that endogenous IL-17A contributes to the development of allergen-induced airway hyperresponsiveness and there is also evidence that IL-17A stimulates the release of several cytokines with known capacity for airway remodelling, from cells normally residing in the airways. New studies are required to determine whether these effects on local cells actually contribute to airway remodelling in vivo. If this is the case, then IL-17A may constitute a useful target for pharmacotherapeutic intervention in allergic airway disease.