Non-signaling receptor for IL1A, IL1B and IL1RN. Reduces IL1B activities. Serves as a decoy receptor by competitive binding to IL1B and preventing its binding to IL1R1. Also modulates cellular response through non-signaling association with IL1RAP after binding to IL1B. IL1R2 (membrane and secreted forms) preferentially binds IL1B and poorly IL1A and IL1RN. The secreted IL1R2 recruits secreted IL1RAP with high affinity; this complex formation may be the dominant mechanism for neutralization of IL1B by secreted/soluble receptors. Associates with IL1RAP to form a non-signaling interleukin-1 receptor complex. A soluble form (sIL1R2) can also be produced by proteolytic cleavage at the cell surface (shedding) involving a metalloproteinase; hovever, several sIL1R2 forms ranging from 45 and 60 kDa are reported. Belongs to the interleukin-1 receptor family.