IL-33, also known as NF-HEV and DVS 27, is a 17.5 kDa proinflammatory protein that may also regulate gene transcription. DVS 27 was identifed as a gene that is upregulated in vasospastic cerebral arteries. NF-HEV was described as a nuclear factor that is preferentially expressed in the endothelial cells of high endothelial venules relative to endothelial cells from other tissues. IL-33 was identified based on sequence and structural homology with IL-1 family cytokines. DVS 27, NF-HEV, and IL-33 share 100% amino acid sequence identity. IL-33 is constitutively expressed in smooth muscle and airway epithelia. It is up?regulated in arterial smooth muscle, dermal fibroblasts, and keratinocytes following IL-1 alpha or IL?1 beta stimulation. Similar to IL-1, IL-33 can be cleaved in vitro by caspase, generating an N?terminal fragment that is slightly shorter than the Cterminal fragment. The N?terminal portion of full length IL-33 contains a predicted bipartite nuclear localization sequence and a homeodomain-like helix-turn-helix DNA binding domain. By immunofluorescence, full length IL-33 localizes to the nucleus in HUVECs and transfectants. The C?terminal fragment, corresponding to mature IL-33, binds and triggers signaling through mast cell IL?1 R4/ST2L, a longtime orphan receptor involved in the augmentation of Th2 cell responses. A ternary signaling complex is formed by the subsequent association of IL-33 and ST2L with IL?1 RAcP. Stimulation of Th2 polarized lymphocytes with mature IL-33 in vitro induces IL-5 and IL-13 secretion. In vivo administration of mature IL-33 promotes increased production of IL-5, IL-13, IgE, and IgA, as well as splenomegaly and inflammatory infiltration of mucosal tissues.

高纯度、高活性、低内毒素、高批间一致性

-25 ~ -15℃保存，收到货之后有效期1年。 复溶后，无菌条件下，2~8℃保存，7天有效期。复溶后， 无菌条件下，-85 ~ -65℃保存，3个月有效期。