Recombinant human IL-18 protein

Recombinant Human Interleukin-18 protein (with HSA)

Interleukin 18 (IL-18; formerly called interferon-g inducing factor) is a pro-inflammatory cytokine that causes a variety of biological effects associated with infection and inflammation [1, 2]. More specifically, IL-18 induces IFN-γ production and contributes to T-helper 1 (Th1) cell polarization.

IL-18 is produced by macrophages and other cells, as a proprotein which is proteolytically processed to its active form by caspase 1, an enzyme that is activated within the inflammasome multiprotein complex. IL-18 binds to an heterodimeric receptor consisting of IL-18R and IL-18 receptor accessory protein, leading to the activation of NF-kB and AP-1 [3].

Recombinant human IL-18 is a 157 amino acid protein with a molecular mass of 18 kDa that is produced in Escherichia coli. It is used to induce its cognate signalling pathway in HEK-Blue™ IL-18 cells.

References:

1. Arend W. et al., 2008. IL-1, IL-18, and IL-33 families of cytokines. Immunol Rev. 223:20-38.
2. Dinarello CA. et al., 1998. Overview of interleukin-18: more than an interferon-gamma inducing factor.J Leukoc Biol. 63(6):658-64.
3. Gracie JA. et al., 2003. Interleukin-18. J Leukoc Biol.3(2):213-24.

Figures

SDS PAGE of the recombinant human (h)IL-18 protein. 1.5 μg of hIL-18 was loaded on a 12% Mini-PROTEAN® TGX Stain-Free™ Precast Gel (Bio-Rad) stained with Coomassie. Detection was performed as per the manufacturer’s instructions. A band was detected at ~18 kDa.

Dose-response in HEK-Blue™ IL-18 cells to recombinant IL-18 cytokine. Cells were stimulated with increasing concentrations of recombinant human IL-18. After overnight incubation, the NF-κBinduced SEAP activity was determined using QUANTI-Blue™, a SEAP detection reagent. Data are shown as optical density (OD) at 650 nm (mean ± SEM).

Specifications

Source: E. coli

Uniprot ID: Q14116

Formulation: Lyophilized from a 0.2 μm filtered solution in PBS (pH 7.4) with human serum albumin (HSA) as a carrier protein

Purity: >95%, by SDS-PAGE

Molecular mass: ~ 18.3 kDa

Solubility: 100 μg/ml in water

Endotoxin level: < 0.1 EU/μg protein as determined by the LAL method

Bioactivity: Validated using HEK-Blue IL-18 cells

Contents

• 10 μg of recombinant human IL-18 provided as a white lyophilized powder.
• 1.5 ml endotoxin-free water.

Recombinant human IL-18 is shipped at room temperature.

Upon receipt it should be stored at -20 °C.