• Species Reactivity

  Human

• Specificity

  Detects human IL-18/IL-1F4 in direct ELISAs.

• Source

  Monoclonal Mouse IgG    _2A Clone # 914205

• Purification

  Protein A or G purified from hybridoma culture supernatant

• Immunogen

  Human  IL-18/IL-1F4 synthetic peptide    
  Accession # Q14116

• Formulation

  Lyophilized from a 0.2 μm filtered solution in PBS with Trehalose. *Small pack size (SP) is supplied as a 0.2 µm filtered solution in PBS.

• Endotoxin Level

  <0.10 EU per 1 μg of the antibody by the LAL method.  

• Label

  Unconjugated

Applications

• 
  

  Recommended    
  Concentration

  Sample

• Neutralization

  Measured by its ability to neutralize IL‑18/IL‑1F4-induced IFN‑ gamma secretion in the KG‑1 human acute myelogenous leukemia cell line. Novick, D.     et al. (1999) Immunity     10(1):127. The Neutralization Dose (ND    ₅₀) is typically    
  3‑15 µg/mL in the presence of 10 ng/mL Recombinant Human IL‑18/IL‑1F4 and 20 ng/mL Recombinant Human TNF‑ alpha.

Please Note: Optimal dilutions should be determined by each laboratory for each application.  are available in the Technical Information section on our website.

Data Examples

Preparation and Storage

• Reconstitution

  Reconstitute at 0.5 mg/mL in sterile PBS.

• Shipping

  The product is shipped at ambient temperature. Upon receipt, store it immediately at the temperature recommended below. *Small pack size (SP) is shipped with polar packs. Upon receipt, store it immediately at -20 to -70 °C

• Stability & 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.

• 6 months, -20 to -70 °C under sterile conditions after reconstitution.

Background: IL-18/IL-1F4

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).

• References:

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.

• Long Name:

  Interleukin 18

• Entrez Gene IDs:

  3606 (Human); 16173 (Mouse); 29197 (Rat); 397057 (Porcine); 574151 (Primate)

• Alternate Names:

  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