IL-25 (also known as IL-17E) is a member of the IL-17 family of proinflammatory cytokines, which includes IL-17A, IL-17B, IL-17C, IL-17F and IL-17A/F. IL-17E is found at low levels in various peripheral tissues. It is a proinflammatory cytokine that promotes airway eosinophilia in mice. IL-17E plays a role in Th2 type inflammatory diseases, such as asthma and atopic dermatitis. IL-25 induces elevatedgene expression of IL-4, IL-5 and IL-13 in multiple tissues and results in T helper 2 (TH2)-