Interleukin-33: increasing role in dermatological conditions.

Interleukin-33 is a novel and an unconventional member of IL-1 family. It is an inflammation-induced factor with dual function exercising its role as an intracellular regulator of gene expression, as well as, an extracellular alarm mediator. It is a ligand for ST2, a heterodimeric membrane-bound receptor of the orphan IL-1 family receptor. Interleukin-33/ST2 signaling has been studied in a wide range of inflammatory skin conditions for its crucial role in immune responses and tissue homeostasis. In this review, we report the current knowledge regarding the complex biology of interleukin-33 and its function in the skin and in clinical settings.