Interleukin 18

Interleukin-18 (IL-18) is a cytokine produced by macrophages and other cells that belongs to the IL-1 superfamily. IL-18 works together with IL-12 to induce cell-mediated immunity following infection with microbial products like lipopolysaccharide (LPS). After stimulation with IL-18, natural killer (NK) cells and certain T cells release another important cytokine called interferon-γ (IFN-γ) or type II interferon that plays an important role in activating the macrophages or other cells. Apart from its physiological role, IL-18 is also able to induce severe inflammatory reactions, which suggests its role in certain inflammatory disorders.