Interleukin (IL)-1β is a cytokine involved in immune regulation and inflammatory responses in a variety of tissues and disease and is the canonical member of the IL-1 family of cytokines. The IL-1 family cytokines 1F6, IL-1F8 and IL-1F9 are known to be ligands for IL-1 receptor related protein 2 (IL-1 Rrp2) giving rise to signalling similar to that of IL-1β via IL-1 receptor type 1 (IL-1RI). However, the biological activity of these novel ligands is yet to be characterized but it is reasonable to assume that they, like IL-1β, may play a role In the pathogenesis of inflammatory disease and may therefore be viable therapeutic targets.