Illustration of a therapeutic antibody (blue) blocking interleukin 11 (IL-11, orange), which belongs to a group of signalling proteins known as cytokines. IL-11 has a variety of functions, including the promotion of inflammation. Its overexpression is associated with certain autoimmune diseases, fibrotic diseases (abnormal scar formation) and cancers. As such, IL-11 is a potential therapeutic target. A study in 2024 found that inhibiting its expression in mice extended the mice's lifespan by 25% on average.