IL-18, in synergy with IL-12, induces the synthesis of IFN-γ in NK cells as a response against infections by intracellular microorganisms, but, at the same time, hyperproduction of IL-12 and IL-18 can induce severe phlogistic alterations, and, as such, IL-18 can be considered a proinflammatory cytokine [67]. The gene discussed is IL18; the disease is infection.