IL-1R2 is a type I transmembrane glycoprotein that is expressed predominantly by cells of the myeloid lineage. Like IL-1R1, the extracellular domain of IL-1R2 is capable of binding to all three forms of IL-1 . Unlike IL-1R1, however, membrane-bound IL-1R2 has a short cytoplasmic tail and does not transduce signals upon binding IL-1 but rather functions as a decoy receptor to dampen IL-1 signaling . As a negative regulator of the IL-1 receptor signaling complex, research studies have also demonstrated that membrane-bound IL-1R2 undergoes regulated intramembrane proteolysis in response to pro-inflammatory molecules. This process converts the extracellular domain of IL-1R2 into a soluble decoy receptor capable of binding IL-1, limiting its capacity to elicit productive signals through membrane-bound IL-1R1 . Recent studies have demonstrated that some types of human cancers are enriched with regulatory T cells that express high levels of IL-1R2, an attribute that may contribute to their role in immunosuppression .