| Field | Specification |
|---|---|
| Biological Activity | |
| Endotoxin Level | |
| Formulation | |
| Molecular Weight | |
| Product Type | |
| Purity | |
| Reconstitution | |
| Source | Escherichia coli |
| Storage |
Scientific Background
Interleukin-18 (IL18, also known as interferon-gamma inducing factor or IGIF) is a cytokine that belongs to the IL-1 superfamily and is produced by macrophages and other cells. Its biological activity is pleiotropic and it has been shown to induce interferon-gamma production in KG-1 cells. The combination of this cytokine and IL12 has been shown to inhibit IL4 dependent IgE and IgG1 production, and enhance IgG2a production in B cells.Recombinant rat Interleukin-18 (rrIL-18) produced in E.coli is a single non-glycosylated polypeptide chain containing 159 amino acids.
Product Description
E. coli ExpressionRecombinant IL-18 Rat protein is produced using a validated E. coli expression system and supplied as lyophilized powder for long-term stability. Suitable for use in functional bioassays, ELISA standard curves, receptor binding studies, antibody validation, and related research applications.
Protein Specifications
| Expression System | E. coli |
|---|---|
| Molecular Weight | 18.4 kDa, observed by reducing SDS-PAGE. |
| Purity | > 95% by SDS-PAGE analyses. |
| Endotoxin | < 0.2 EU/μg, determined by LAL method. |
| Physical Form | Sterile Filtered White lyophilized (freeze-dried) powder. |
| Formulation | Lyophilized after extensive dialysis against 50mM Tris, 50mM NaCl, pH8.0. |
| Reconstitution | Reconstituted in ddH2O at 100 μg/ml. |
| Storage | Lyophilized recombinant ratInterleukin-18 (rrIL-18) remains stable up to 6 months at -80°C from date… |
Functional Activity
ED50 <2μg/ml resulted in the secretion of 0.15 ng/ml h-IFN-gamma when tested using KG-1 cell line, corresponding to a specific activity of > 500 units/mg.
Safety & Handling
This material is offered by USA Bioworld biotech for research, laboratory or further evaluation purposes. For research use only.
This protein was produced in E. coli expression system. Expression system selection determines glycosylation profile, folding, and post-translational modifications. For cell-based stimulation assays, verify the expression system matches the glycosylation requirements of your target receptor or pathway.
Reconstituted in ddH2O at 100 μg/ml. Reconstitute in sterile distilled water or PBS at 100 µg/mL as a standard starting concentration. Allow to dissolve at 4°C for 30 minutes without vortexing. Prepare working aliquots in 0.1% BSA carrier protein and store at −80°C.
This protein has been validated for functional bioactivity: ED50 <2μg/ml resulted in the secretion of 0.15 ng/ml h-IFN-gamma when tested using KG-1 cell line, corresponding to a specific activity of > 500 units/mg.. Optimal working concentrations may vary depending on your cell type, assay format, and culture conditions. Titrate the protein in a dose-response experiment to determine the optimal concentration for your system.
Endotoxin level is < 0.2 EU/μg, determined by LAL method. as determined by the LAL method. Low endotoxin is critical for cell-based studies because endotoxin activates NF-κB and TLR4 signalling in immune cells, producing artefactual cytokine induction that can completely mask the true biological activity of the recombinant protein.
Lyophilized recombinant ratInterleukin-18 (rrIL-18) remains stable up to 6 months at -80°C from date of receipt. Upon reconstitution, rrIL-18 should be stable up to 2 weeks at 4°C or up to 3 months at Upon receipt, immediately store at −80°C. Prepare single-use working aliquots to avoid repeated freeze-thaw cycles. Lyophilized protein is stable for 6–12 months at −80°C from the date of receipt.
BioHippo offers flexible sourcing options for qualified research institutions and partners. The following may be available subject to supplier capabilities and order volume.
- Custom quantities: Bulk pricing or non-standard sizes available for high-throughput screening or scale-up projects.
- Custom formulation: Alternative reconstitution buffers or carrier proteins may be accommodated on request.
- Extended QC data: Additional bioactivity assay data, endotoxin reports, or SEC-HPLC purity profiles available on request.
Contact BioHippo customer support to discuss your requirements.
Research budgets are tight — we get it. That's why we've put together a fresh round of exclusive promotions designed to help you stock up on the reagents, kits, and consumables your lab depends on, without stretching your budget.
🔬 What's on offer right now:
10% Off Pre-Designed siRNA Sets — use code SIRNA10
20% Off Transmembrane Proteins — use code TM20
$50 Off All ELISA Kits — auto-applied at checkout (code ELISA50)
50% Off Lab Consumables + Free Shipping on orders $500+
15% Off Proteins from Trusted Suppliers — use code PROTEIN15
$99 Pipette Filler Promotion Package (reg. $236)
Save 10% on your first order of any R&D grade DENARASE® with code DENARASE10 at checkout.
