The protein encoded by this gene is a member of the interleukin 1 cytokine family. This cytokine can bind to, and may be a ligand for interleukin 18 receptor (IL18R1/IL-1Rrp). This cytokine also binds to interleukin 18 binding protein (IL18BP), an inhibitory binding protein of interleukin 18 (IL18), and subsequently forms a complex with IL18 receptor beta subunit, and through which it inhibits the activity of IL18. This gene along with eight other interleukin 1 family genes form a cytokine gene cluster on chromosome 2. Five alternatively spliced transcript variants encoding distinct isoforms have been reported.,IL37,FIL1,FIL1(ZETA),FIL1Z,IL-1F7,IL-1H,IL-1H4,IL-1RP1,IL-37,IL1F7,IL1H4,IL1RP1,Cell Biology & Developmental Biology,Growth factor,Immunology & Inflammation,Cytokines,Interleukins,Cell Intrinsic Innate Immunity Signaling Pathway,IL37