Protein A or G purified from cell culture supernatant
E. coli-derived recombinant human IL-18/IL-1F4 Tyr37-Asp197 Accession # Q14116
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.
<0.10 EU per 1 μg of the antibody by the LAL method.
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 (ND50) is typically 0.05‑0.3 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. General Protocols are available in the Technical Information section on our website.
IFN-gamma Secretion Induced by IL-18/IL-1F4 and Neutralization by Human IL-18/IL-1F4 Antibody. In the presence of Recombinant Human TNF-alpha (20 ng/mL, Catalog # 210-TA), Recombinant Human IL-18/IL-1F4 (Catalog # 9124-IL) stimulates IFN-gamma secretion in the KG-1 human acute myelogenous leukemia cell line in a dose-dependent manner (orange line), as measured by the Human IFN-gamma Quantikine ELISA Kit (Catalog # DIF50). Under these conditions, IFN-gamma secretion elicited by Recombinant Human IL-18/IL-1F4 (10 ng/mL) is neutralized (green line) by increasing concentrations of Rabbit Anti-Human IL-18/IL-1F4 Monoclonal Antibody (Catalog # MAB9124). The ND50 is typically 0.05-0.3 µg/mL.
Preparation and Storage
Reconstitute at 0.5 mg/mL in sterile PBS.
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.
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).
Dinarello, C.A. et al. (2013) Front. Immunol. 4:289.
Smith, D.E. (2011) J. Leukoc. Biol. 89:383.
Gu, Y. et al. (1997) Science 275:206.
Torigoe, K. et al. (1997) J. Biol. Chem. 272:25737.
Cheung, H. et al. (2005) J. Immunol. 174:5351.
Novick, D. et al. (1999) Immunity 10:127.
Fehniger, T.A. et al. (1999) J. Immunol. 162:4511.
Yoshimoto, T. et al. (1998) J. Immunol. 161:3400.
Yoshimoto, T. et al. (2000) Nat. Immunol. 1:132.
Kroeger, K.M. et al. (2009) J. Leukoc. Biol. 86:769.
Lalor, S.J. et al. (2011) J. Immunol. 186:5738.
Li, J. et al. (2004) Cell. Immunol. 227:103.
Elbim, C. et al. (2005) Clin. Diagn. Lab. Immunol. 12:436.
Fabbi, M. et al. (2015) J. Leukoc. Biol. 97:665.
Ushio, S. et al. (1996) J. Immunol. 156:4274.
Gaggero, A. et al. (2004) Oncogene 23:7552.
Bellora, F. et al. (2012) Eur. J. Immunol. 42:1618.
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