| Human interleukin 33 (IL-33) is a cytokine of the IL-1 superfamily,which is also known as NF-HEV, nuclear factor (NF) in high endothelial venules' (HEVs) and DVS27, a protein that is upregulated in vasospastic cerebral arteries. IL-33, NF-HEV and DVS27 refer to the same protein that is expressed primarily by endothelial and smooth muscle cells in the vasculature and airway. IL-33 mediates its biological effects via IL-1 receptor ST 2, activates NF-kappaB and MAP kinases, and drives production of type 2 cytokines (e.g.IL4,IL-5 and IL-13) from polarized Th2 cells, leading to severe pathological changes in mucosal organs.
Human IL-33 consists of an N-terminal nuclear localization signal (NLS), a helix-turn-helix (HTH) motif, and a C-terminal region with structural homology to IL-1 family cytokines. The C-terminal fragment serves as a cytokine which can be generated by the cleavage of caspase-1 in vitro. IL-33 exhibits both nuclear and extracellular functions.
·Description
Recombinant Human IL-33 produced in E. coli is a single, non-glycosylated, polypeptide chain containing 159 amino acids and having a molecular mass of 18kDa.
·Quality Control
Biological activity: The ED50 of rhIL33 as determined by proliferation of D10.G4.1 mouse helper T cells costimulated with B71/Fc Chimera and antiCD3 was < 2ng/ml, corresponding to a Specific Activity of 5.0 x 105 IU/mg.
Purity: Greater than 95.0% as determined by:
(a) Analysis by RP-HPLC.
(b) Analysis by reducing and non-reducing SDS-PAGE Silver Stained gel.
Amino-Acid Sequence: The sequence of the first five N-terminal amino acids was determined and was found to be Ser-Ile-Thr-Gly-Ile.
Endotoxin: Less than 0.1ng/μg (IEU/μg) of rHuIL-33 as determined by LAL test.
·Formulation
Sterile and Lyophilized aliquots with a 0.2um filtered protein solution containing 20mM PB pH 7.4,1mM EDTA.
·Reconstitution
It is recommended to reconstitute the lyophilized rHuIL-33 in sterile 18MΩ-cm H2O not less than 100μg/ml, which can then be further diluted to working solutions.
·Storage
Lyophilized rHuIL-33 although stable at room temperature for 3 weeks, should be stored desiccated below -18°C. Upon reconstitution rHuIL-31 should be stored at 4°C between 2-7 days and aliquots of reconstituted samples are stable up to 3 months below -18°C for future use.
Please avoid freeze-thaw cycles. |
