Recombinant Human IL-18 BPa His-tag Protein, CF

Recombinant Human IL‑18 BPa His-tag (Catalog # 11236-BP) has a molecular weight (MW) of 33.7 kDa as analyzed by SEC-MALS, suggesting that this protein is a monomer. MW may differ from predicted MW due to post-translational modifications (PTMs) present (e.g. Glycosylation).

Measured by its ability to inhibit the IL-18-induced response of KG-1 Human Acute Myelogenous Leukemia cells . The ED50 for this effect is 5.00-30.0 ng/mL in the presence of 20 ng/mL of Recombinant Human IL-18.

2 μg/lane of Recombinant Human IL-18 BPa His-tag Protein (Catalog # 11236-BP) was resolved with SDS-PAGE under reducing (R) and non-reducing (NR) conditions and visualized by Coomassie® Blue staining, showing bands at 44-51 kDa.

• Reactivity: Hu
• Applications: Bioactivity
• Format: Carrier-Free

Recombinant Human IL-18 BPa His-tag Protein, CF Summary

• Details of Functionality: Measured by its ability to inhibit the IL-18-induced response of KG-1 human acute myelogenous leukemia cells. The ED₅₀ for this effect is 5.00-30.0 ng/mL in the presence of 20 ng/mL of recombinant human IL-18.
• Source: Human embryonic kidney cell, HEK293-derived human IL-18 BPa protein
  Thr31-Gly194, with a C-terminal 6-His tag
• Accession #: O95998.2
• N-terminal Sequence: Thr31
• Protein/Peptide Type: Recombinant Proteins
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining
• Endotoxin Note: <0.10 EU per 1 μg of the protein by the LAL method.

Applications/Dilutions

• Dilutions:
  • Bioactivity
• Theoretical MW: 18 kDa.
  Disclaimer note: The observed molecular weight of the protein may vary from the listed predicted molecular weight due to post translational modifications, post translation cleavages, relative charges, and other experimental factors.
• SDS-PAGE: 44-51 kDa, under reducing conditions.

Packaging, Storage & Formulations

• Storage: Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
  • 12 months from date of receipt, -20 to -70 °C as supplied.
  • 1 month, 2 to 8 °C under sterile conditions after reconstitution.
  • 3 months, -20 to -70 °C under sterile conditions after reconstitution.
• Buffer: Lyophilized from a 0.2 μm filtered solution in PBS with trehalose.
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining
• Reconstitution Instructions: Reconstitute at 500 μg/mL in PBS.

Notes

This product is produced by and ships from R&D Systems, Inc., a Bio-Techne brand.

Alternate Names for Recombinant Human IL-18 BPa His-tag Protein, CF

• IL18 BPa
• IL-18 BPa
• IL18BP
• IL-18BP
• IL18BPa
• interleukin 18 binding protein
• interleukin-18-binding protein
• MC51L-53L-54L homolog gene product
• tadekinig-alfa

Background

IL-18 Receptor alpha (IL-18 Ra), also known as IL-18 R1, IL-1 R5, and IL-1 Rrp, is a transmembrane component of the IL-18 Receptor (1). It associates with IL‑18 Rb/IL‑1 R7 to form the high affinity receptor complex for IL-18 and confer cellular responsiveness to IL-18 (2, 3). IL-18 is a member of the IL-1 family of cytokines and shares numerous immunoregulatory functions with IL-12. Mature human IL-18 Ra consists of a 308 amino acid (aa) extracellular domain (ECD) with three immunoglobulin-like domains, a 21 aa transmembrane segment, and a 191 aa cytoplasmic domain (4). Within the ECD, human IL-18 Ra shares 56% aa sequence identity with mouse and rat IL-18 Ra. IL-18 Ra is widely expressed on epithelial cells as well as on B cells, NK cells, CD4+ and CD8+ T cells, and dendritic cells (5-8). Signaling through the IL-18 receptor promotes a Th1 biased immune response and NK cell cytolytic activity (6, 7, 9-11). It also contributes to cigarette smoke-induced airway inflammation and epithelial damage (12). 

1. Dinarello, C.A. et al. (2013) Front. Immunol. 4:289.
2. Torigoe, K. et al. (1997) J. Biol. Chem. 272:25737.
3. Born, T.L. et al. (1998) J. Biol. Chem. 273:29445.
4. Parnet, P. et al. (1996) J. Biol. Chem. 271:3967.
5. Kunikata, T. et al. (1998) Cell Immunol. 189:135.
6. Smeltz, R.B. et al. (2001) J. Exp. Med. 194:143.
7. Chan, W.L. et al. (2001) J. Immunol. 167:1238.
8. Kaser, A. et al. (2004) Blood 103:648.
9. Tomura, M. et al. (1998) J. Immunol. 160:3759.
10. Yoshimoto, T. et al. (1998) J. Immunol. 161:3400.
11. Hyodo, Y. et al. (1999) J. Immunol. 162:1662.
12. Kang, M.J. et al. (2007) J. Immunol. 178:1948.

Bioinformatics

• Uniprot:
  • O95998.2()