Il-18 is a type of interleukin, which is a group of cytokines that play a crucial role in the immune system. Specifically, Il-18 is involved in the activation of immune cells, particularly T cells and natural killer cells. It helps regulate inflammatory responses and is important for fighting infections. Research has shown that Il-18 can influence various diseases, including autoimmune disorders and certain cancers. By promoting the production of other cytokines, Il-18 helps coordinate the body's defense mechanisms. Understanding its functions can lead to new therapeutic approaches for managing immune-related conditions.