Interleukin-18 (IL-18) is a cytokine that belongs to the IL-1 superfamily and is produced by macrophages and other cells. IL-18 works by binding to the IL-18 receptor, and together with IL-12 that it induces cell-mediated immunity following infection with microbial products like lipopolysaccharide (LPS). After stimulation with IL-18, natural killer (NK) cells and certain T cells release another important cytokine called interferon gamma or type II interferon that plays an important role in activating the macrophages or other cells. The combination of this cytokine and IL-12 has been shown to inhibit IL-4 dependent IgE and IgG1 production, and enhance IgG2a production in B cells. IL-18 binding protein (IL-18BP) can specifically interact with this cytokine, and thus negatively regulate its biological activity.

Sequence:
MYFGKLESKLSVIRNLNDQVLFIDQGNRPLFEDMTDSDCRDNAPRTIFIISMYKDSQPRGMAVTISVKCEKISTLSCENKIISFKEMNPPDNIKD
TKSDIIFFQRSVPGHDNKMQFESSSYEGYFLACEKERDLFKLILKKEDELGDRSIMFTVQNED with polyhistidine tag at the C-terminus

Source:
Escherichia coli
Animal-free reagent and laboratory
Manufactured and tested under GMP guideline

Endotoxin level:
<0.1 EU per 1 μg of the protein by the LAL method. Activity:
Measure by its ability to induce IFN gamma secretion in KG-1 cells. The ED₅₀ for this effect is <5 ng/mL. Purity:
>98% as determined by SDS-PAGE. Purified by Ni-NTA chromatography.

Mycoplasma:
Negative when tested by PCR detection method.

Formulation:
Lyophilized from a 0.22 μm filtered solution of 1X PBS, pH 8.0.

Reconstitution:
It is recommended to reconstitute the lyophilized protein in sterile H₂O to a concentration not less than 100 μg/mL and incubate the stock solution for at least 20 min to ensure sufficient re-dissolved.

Storage:
Lyophilized protein should be stored at -20°C. This product is stable for one year upon receipt, when handled and stored as instructed. Upon reconstitution, protein aliquots should be stored at -20°C or -80°C. Avoid repeated freeze/thaw cycles.

Note:
Please use within one month after protein reconstitution.

Specification:
Croyez GMP® recombinant proteins are manufactured in ISO 13485:2016 and GMP-certified facility.
The processes include:
● Testing and traceability of raw material
● Records of the maintenance and equipment calibration
● Personnel training records
● Batch-to-batch consistency
● Documentation of QA control and process changes
● Manufactured and tested under an ISO 13485:2016 certified quality management system
● Stability monitor of product shelf-life

Reference:
1. Takahashi HK. et al. (2004) Clin Immunol. 12: 30-4.
2. Dinarello CA. et al. (2013) Front Immunol. 4: 289.
3. Son YI. et al. (2001) Cancer Res. 61,3: 884-8.
4. Fukao T. et al. (2000) J Immunol. 164: 64-71.
5. Kaplanski G. (2018) Immunol Rev. 281,1: 138-153.

Data Sheet