Intermediate-affinity interleukin-2 receptor complex (IL-2Rβγ)

The intermediate-affinity interleukin-2 receptor complex is a heterodimeric signaling unit composed of the IL-2 receptor beta subunit (CD122) and the common gamma chain (CD132) (Source: UniProt, PubMed). Unlike the high-affinity trimeric receptor that includes the alpha subunit (CD25), this complex is primarily expressed on resting memory CD8+ T cells and natural killer (NK) cells (Source: NIH). Upon binding its ligand, interleukin-2 (IL-2), the complex initiates intracellular signaling through the JAK1 and JAK3 kinases, leading to the phosphorylation of STAT5 and the activation of genes involved in cell proliferation and survival (Source: StatPearls). In oncology, this receptor complex is a critical target for next-generation IL-2 immunotherapies designed to selectively expand effector immune cells while avoiding the activation of immunosuppressive regulatory T cells (Tregs) which constitutively express the high-affinity receptor (Source: Nature Reviews Drug Discovery). By bypassing the alpha subunit, these biased agonists aim to enhance anti-tumor immunity and improve the therapeutic index by reducing severe side effects like vascular leak syndrome (Source: Journal of Immunotherapy of Cancer). Consequently, the intermediate-affinity receptor serves as a focal point for developing more precise and less toxic cytokine-based treatments for various solid tumors.

Other names

IL-2RβγCD122/CD132 complexInterleukin-2 receptor beta-gamma heterodimerIntermediate-affinity IL-2 receptorIL-2R beta-gamma complex

Agonism of the beta (CD122) and gamma (CD132) subunits to trigger downstream JAK/STAT signaling, specifically activating effector T cells and NK cells while minimizing activation of regulatory T cells.