Regulatory T cells and regulation of allergic airway disease.

Diseases like asthma have dramatically increased in the last decades. The reasons for the rising prevalence are still controversially discussed. Besides the genetic predisposition a number of different causes are thought to affect the increase of allergies. These include the hygiene hypothesis as well as changes in intestinal microbiota. Allergic airway inflammation is driven by T cells but it has become clear that tolerance and also suppression of allergic inflammation are mediated by so called regulatory T cells (Tregs). Indeed, naturally occurring Treg as well as induced Tregs have been shown to suppress allergic airway disease. In addition, the effectiveness of different therapeutic strategies (e.g. allergen immunotherapy) are mediated via Tregs. In addition, several Treg based approaches have been shown to effectively suppress allergic airway disease in different models. However, more research is needed to explore these potentially interesting approaches for the treatment of human disease.