protein_function: Augments natural killer cell activity in spleen cellsand stimulates interferon gamma production in T-helper type Icells.
Interleukin(IL)-18, also called Interferon-gamma-inducing factor(IGIF), augments natural killer(NK) activity in spleen cells. The gene encodes a precursor protein of 192 amino acids and a mature protein of 157 amino acids.1 IL-18 is a recently discovered cytokine that modulates both T helper type 1(Th1) and Th2 responses.2 IL-18 is a potent proinflammatory cytokine with potential atherogenic properties. It is highly expressed in the atherosclerotic plaques compared with control normal arteries and is localized mainly in plaque macrophages.3