IL-1 Receptor Accessory Protein (IL1RAP) is a member of the IL-1 receptor family, a co-receptor of the IL-1 (alpha and beta), IL-33 and IL-36 receptors involved in IL-1 signaling, activating different signaling pathways implicated in inflammation and proliferation. IL1RAP is critical for mediating the effects of IL-33, through the ST2/IL1RAP complex, and IL-36, through the IL-1Rrp2/IL1RAP complex.
Human IL1RAP is composed of 3 domains: an extracellular domain (ECD, 347 AA), a transmembrane part (21 AA), and a cytoplasmic domain (182 AA). IL1RAP has been identified as a marker of interest in the context of Chronic Myeloid Leukemia (CML) treatment, activating NK cells and blocking tumor growth. Its over expression is demonstrated in Hematopoietic Stem and Progenitor Cells (HSPC) and also in Acute Myeloid Leukemia (AML) disease.