CellaQuantTM Human IL-18 (Interleukin 18) ELISA Kit

Interleukin-18 (IL-18), originally termed interferon-gamma-inducing factor, is a key pro-inflammatory cytokine of the IL-1 family. Synthesized as an inactive precursor, its maturation requires cleavage by caspase-1, and it is released during pyroptosis via GSDMD pores, linking it to innate immune danger signals. Mature IL-18 signals through a receptor complex (IL-18R1/IL-18RAP), activating a MyD88/NF-κB pathway that drives inflammatory gene expression. Its most critical function is the potent synergy with IL-12 to induce high-level interferon-gamma (IFN-γ) production from T-helper 1 (Th1) cells and natural killer (NK) cells, defining its central role in Th1-type immunity. IL-18 also enhances NK cell cytotoxicity and regulates other cytokines like GM-CSF and IL-10. While promoting Th1 responses, it can also influence Th2 differentiation under specific conditions. Due to this potent activity, dysregulated IL-18 is implicated in autoimmune diseases (e.g., inflammatory bowel disease, psoriasis), metabolic syndromes, sepsis, and cancer progression. Therefore, therapeutic neutralization of IL-18 is a promising strategy for treating inflammation-driven pathologies.

This ELISA kit uses the Sandwich-ELISA principle. The micro ELISA plate provided in this kit has been pre-coated with an antibody specific to Human IL-18. Samples (or Standards & Quality Control Material) are added to the micro ELISA plate wells and combined with the specific antibody. Then a biotinylated detection antibody specific for Human IL-18 and Avidin-Horseradish Peroxidase (HRP) conjugate are added successively to each micro plate well and incubated. Free components are washed away. The substrate solution is added to each well. Only those wells that contain Human IL-18, biotinylated detection antibody and Avidin-HRP conjugate will appear blue in color. The enzyme-substrate reaction is terminated by the addition of stop solution and the color turns yellow. The optical density (OD) is measured spectrophotometrically at a wavelength of 450±2 nm. The OD value is proportional to the concentration of Human IL-18. You can calculate the concentration of Human IL-18 in the samples by comparing the OD of the samples to the standard curve.

This ELISA kit applies to the in vitro quantitative determination of Human IL-18 concentrations in Cell culture supernatant, Cell lysates or other biological fluids.