Purified anti-human IL-33

IL-33, also known as NFHEV and DVS 27, is a 30 kD proinflammatory protein that belongs to IL-1 superfamily. IL-33 is constitutively expressed in smooth muscle and airway epithelia. It is upregulated in arterial smooth muscle, dermal fibroblasts, and keratinocytes following IL1alpha or IL1beta stimulation. IL-33 interacts with IL1RL1/ST2 receptor and IL-1 receptor accessory protein (IL1RAP) in order to activate intracellular molecules in the NF-kappaB and MAP kinase signaling pathways that drive production of type 2 cytokines (e.g. IL-5 and IL-13) from polarized Th2 cells. Recombinant IL-33 has been shown to enhance Th2-associated immune responses and potently increase mast cell proliferation and cytokine production.