Recombinant Human IL-1 beta / IL-1F2 Protein, Tag Free, low endotoxin, 20µg

Background
Interleukin-1 beta (IL-1β) is also known as catabolin, is a cytokine protein that in humans is encoded by the IL1B gene. IL-1β precursor is cleaved by caspase 1 (interleukin 1 beta convertase). Cytosolic thiol protease cleaves the product to form mature IL-1 beta. IL1β are structurally related polypeptides that share approximately 21% amino acid (aa) identity in human. Both proteins are produced by a wide variety of cells in response to inflammatory agents, infections, or microbial endotoxins. While IL1α and IL1β are regulated independently, they bind to the same receptor and exert identical biological effects. IL-1β is a member of the interleukin 1 cytokine family. This cytokine is produced by activated macrophages as a proprotein, which is proteolytically processed to its active form by caspase 1 (CASP1/ICE). This cytokine is an important mediator of the inflammatory response, and is involved in a variety of cellular activities, including cell proliferation, differentiation, and apoptosis. The induction of cyclooxygenase-2 (PTGS2/COX2) by this cytokine in the central nervous system (CNS) is found to contribute to inflammatory pain hypersensitivity. This gene and eight other interleukin 1 family genes form a cytokine gene cluster on chromosome 2.

Source
Recombinant  Human IL-1 beta, Tag Free (ILB-H4110) is expressed from E.coli cells. It contains AA Ala 117 - Ser 269 (Accession # P01584-1).
Predicted N-terminus: Met

Molecular Characterization
This protein carries no "tag".
The protein has a calculated MW of 17.5 kDa. The protein migrates as 18 kDa on a SDS-PAGE gel under reducing (R) condition.

Endotoxin
Less than 0.1 EU per μg by the LAL method.

Purity
>95% as determined by SDS-PAGE.

Formulation
Lyophilized from 0.22 μm filtered solution in PBS, pH7.4. Normally Trehalose is added as protectant before lyophilization.

Reconstitution
See Certificate of Analysis for reconstitution instructions and specific concentrations.

Storage
For long term storage, the product should be stored at lyophilized state at -20°C or lower.
Please avoid repeated freeze-thaw cycles.
This product is stable after storage at:
-20°C to -70°C for 12 months in lyophilized state;
-70^°C for 3 months under sterile conditions after reconstitution.

Bioactivity
Please refer to product data sheet.

References

(1) Auron PE., et al., 1984, Proc Natl Acad Sci U S A, 81(24): 7907-11.
(2) March CJ, et al., Nature, 315 (6021): 641–7.
(3) Clark BD., et al., 1986, Nucleic Acids Res, 14(20):7897-914.
(4) Martinon, F., et al., 2007, Cell Death Differ, 14(1): 10-22.