Interleukin-15 receptor system (IL-15R system (often referred to as IL-15 receptor or IL-15R))

The interleukin-15 receptor system is a heterotrimeric cytokine receptor complex critical for immune function. It consists of three subunits: a unique high-affinity alpha subunit (IL-15Rα), a beta subunit (IL-2/15Rβ) shared with IL-2 receptor, and a common gamma subunit (γc) also shared with IL-2, IL-4, IL-7, IL-9, and IL-21 receptors. The receptor mediates signaling for interleukin-15 (IL-15), driving the activation, proliferation, and survival of natural killer cells, CD8+ memory T cells, and other immune cells. IL-15 and its receptor are essential in anti-tumor immunity, viral infection defense, and autoimmune regulation. They share structural similarities and overlapping signaling pathways with the IL-2 system, but IL-15Rα expression is broader and has much higher ligand specificity. The trans-presentation mechanism (where IL-15 bound to IL-15Rα on surface of antigen-presenting cells is presented to neighboring lymphocytes) is central to its function. Dysregulation of the IL-15 receptor system is implicated in cancer, inflammatory diseases, and autoimmunity. Therapeutic drugs targeting this system include IL-15 agonists for cancer immunotherapy and antagonists to suppress unwanted inflammation

Other names

IL-15 receptorInterleukin-15 receptorIL-15RIL-15Rα (for the alpha subunit)IL-2/15Rβ and γc (for shared subunits)

Agonist activity: Stimulation of NK and T cells for anti-cancer and anti-viral immunity Antagonist activity: Inhibition of excessive immune activation in autoimmune disease or inflammation Trans-presentation blockade: Drugs may interfere with IL-15/IL-15Rα complex formation or trans-presentation pathway