Recombinant Human IL-18/IL-1F4 Protein, CF

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

Recombinant Human IL-18/IL-1F4 Protein, CF Summary

• Additional Information: A New rh IL-18 is Available! Competitively priced; Higher purity; Lower endotoxin specifications; Made in-house!
• Details of Functionality: Induction of IFN-gamma by KG-1 cell [human myelomonocyte; ATCC CCL246] in response to the recombinant human IL-18 was measured using human IFN-gamma ELISA. The activity of lot 111 was as follows: IL-18 final concentration 10 ng/mL; IFN-gamma induction 48.1 IU/mL and IL-18 final concentration 20 ng/mL; IFN-gamma induction 64.3 IU/mL.
• Source: E. coli-derived human IL-18/IL-1F4 protein
  37-193 aa
• Protein/Peptide Type: Recombinant Proteins
• Gene: IL18
• Purity: >90%, by SDS-PAGE under reducing conditions and visualized by Colloidal Coomassie® Blue stain.
• Endotoxin Note: <1.0 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.

Packaging, Storage & Formulations

• Storage: Store the unopened product at -70 °C. Use a manual defrost freezer and avoid repeated freeze-thaw cycles. Do not use past expiration date.
• Buffer: 200 μg in 2 mL volume of PBS containing 1% sucrose.
• Purity: >90%, by SDS-PAGE under reducing conditions and visualized by Colloidal Coomassie® Blue stain.

Notes

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

Alternate Names for Recombinant Human IL-18/IL-1F4 Protein, CF

• Iboctadekin
• IFN-gamma-inducing factor
• IGIF
• IGIFIL-1 gamma
• IL18
• IL-18
• IL-18MGC12320
• IL-1F4
• IL1F4iboctadekin
• IL-1g
• Interferon gamma-inducing factor
• interleukin 18 (interferon-gamma-inducing factor)
• Interleukin-1 gamma
• interleukin-18

Background

Interleukin-18 (IL-18) is a proinflammatory cytokine in the IL-1 family that exerts distinct immune effects depending on the local cytokine environment. It is expressed as a 24 kDa precursor by endothelial and epithelial cells, keratinocytes, gamma δ T cells, and phagocytes. The precursor is activated intracellularly by Caspase-1 mediated proteolysis to release the 17 kDa mature cytokine. The precursor can also be released by necrotic cells for extracellular cleavage by multiple proteases.
IL-18 activation is induced by infection or tissue damage and contributes to disease pathology in chronic inflammation (1-3). IL-18 binds to the widely expressed IL-18 R alpha which recruits IL-18 R beta to form the signaling receptor complex (4, 5). Its bioactivity is negatively regulated by interactions with IL-18 binding proteins and virally encoded IL-18BP homologs (6). In the presence of IL-12 or IL-15, IL-18 enhances anti-viral Th1 immune responses by inducing IFN-gamma production and the cytolytic activity of CD8⁺ T cells and NK cells (7, 8). In the absence of IL-12 or IL-15, however, IL-18 promotes production of the Th2 cytokines IL-4 and IL-13 by CD4⁺ T cells and basophils (9, 10). In the presence of IL-1 beta or IL-23, IL-18 induces the antigen-independent production of IL-17 by gamma δ T cells and CD4⁺ T cells (11). IL-18 also promotes myeloid dendritic cell maturation and triggers neutrophil respiratory burst (12, 13). In cancer, IL-18 exhibits diverse activities including enhancing anti-tumor immunity, inhibiting or promoting angiogenesis, and promoting tumor cell metastasis (14). Mature human IL-18 shares approximately 63% amino acid sequence identity with mouse and rat IL-18 (15). Alternative splicing in human ovarian cancer generates an isoform that is resistant to Caspase-1 activation (16). A cell surface form can be expressed on M-CSF induced macrophages and released in response to bacterial endotoxin (17).

1. Dinarello, C.A. et al. (2013) Front. Immunol. 4:289.
2. Smith, D.E. (2011) J. Leukoc. Biol. 89:383.
3. Gu, Y. et al. (1997) Science 275:206.
4. Torigoe, K. et al. (1997) J. Biol. Chem. 272:25737.
5. Cheung, H. et al. (2005) J. Immunol. 174:5351.
6. Novick, D. et al. (1999) Immunity 10:127.
7. Fehniger, T.A. et al. (1999) J. Immunol. 162:4511.
8. Yoshimoto, T. et al. (1998) J. Immunol. 161:3400.
9. Yoshimoto, T. et al. (2000) Nat. Immunol. 1:132.
10. Kroeger, K.M. et al. (2009) J. Leukoc. Biol. 86:769.
11. Lalor, S.J. et al. (2011) J. Immunol. 186:5738.
12. Li, J. et al. (2004) Cell. Immunol. 227:103.
13. Elbim, C. et al. (2005) Clin. Diagn. Lab. Immunol. 12:436.
14. Fabbi, M. et al. (2015) J. Leukoc. Biol. 97:665.
15. Ushio, S. et al. (1996) J. Immunol. 156:4274.
16. Gaggero, A. et al. (2004) Oncogene 23:7552.
17. Bellora, F. et al. (2012) Eur. J. Immunol. 42:1618.

Publications for IL-18/IL-1F4 (B003-2)(4)

Publications using B003-2

• K Jamal Jame, WJ Gallert, SD Yanik, S Panek, J Kronsbein, D Jungck, A Koch, J Knobloch Biomarkers for Comorbidities Modulate the Activity of T-Cells in COPD International Journal of Molecular Sciences, 2021-07-02;22(13):. 2021-07-02 [PMID: 34281240] (Bioassay, Human)
• JW Choi, S Lim, JH Kang, SH Hwang, KC Hwang, SW Kim, S Lee Proteome Analysis of Human Natural Killer Cell Derived Extracellular Vesicles for Identification of Anticancer Effectors Molecules, 2020-11-09;25(21):. 2020-11-09 [PMID: 33182448] (Cell Culture, Human)
• Gonzalez RM, Seurynck-Servoss SL, Crowley SA Development and validation of sandwich ELISA microarrays with minimal assay interference. J. Proteome Res., 2008-04-19;7(6):2406-14. 2008-04-19 [PMID: 18422355] (ELISA (Standard))
• Wu C, Sakorafas P, Miller R, McCarthy D, Scesney S, Dixon R, Ghayur T IL-18 receptor beta-induced changes in the presentation of IL-18 binding sites affect ligand binding and signal transduction. J. Immunol., 2003-06-01;170(11):5571-7. 2003-06-01 [PMID: 12759435] (Binding Assay, Bioassay, Human)

Bioinformatics

• Gene Symbol: IL18