Human Interleukin 18 Receptor 1 (IL18R1) Protein

Background

IL18R1 is a key receptor in the interleukin-18 (IL-18) signaling pathway, mediating pro-inflammatory immune responses and host defense mechanisms. It forms a heterodimeric complex with IL18RAP (Interleukin 18 Receptor Accessory Protein) upon IL-18 ligand binding, leading to the recruitment of the MyD88 adaptor protein and activation of downstream NF-κB, MAPK, and JNK pathways. IL18R1 is highly expressed on immune cells, including T cells, natural killer (NK) cells, and macrophages, where it plays critical roles in cytokine production, immune cell activation, and Th1 immune responses. It contributes to the regulation of inflammation, pathogen defense, and tissue repair in response to infections, stress, and inflammatory stimuli. Dysregulation of IL18R1 is linked to autoimmune diseases, chronic inflammation, and cancers, where excessive IL-18 signaling promotes tissue damage and tumor progression. Knockout studies reveal impaired cytokine production, reduced NK cell activation, and weakened pathogen clearance, underscoring its critical role in innate and adaptive immunity, inflammatory signaling, and immune surveillance.