Selective roles and dysregulation of interleukin-10 in allergic disease.

There is mounting evidence to support a role for interleukin (IL)-10 in the regulation of both allergic and nonallergic immune responses. The current view is that IL-10 influences Th2-driven allergic processes by altering the interplay between Th1 and Th2 effector cells. However, lack of a clear delineation of the different types of IL-10-secreting regulatory T cells poses a major challenge in defining IL-10-mediated immune pathways, which govern the development, persistence, and modulation of allergic status. This is compounded by observations that undermine the credibility of the Th1/Th2 paradigm as a model for allergic disease. Nevertheless, enhanced IL-10 secretion by T cells during conventional immunotherapy, coupled with evidence of a link between genetics and high IL-10 production to a specific allergen, suggests that IL-10 induction is an appropriate goal of therapy. Knowledge of the targeted patient population and design of an immunogen (ie, peptide or modified allergen) within this context are likely to provide improved results over conventional immunotherapy.