Interleukin-2 receptor subunit beta and gamma heterodimer (IL-2Rβγ)

The Interleukin-2 receptor subunit beta and gamma heterodimer (IL-2Rβγ) is a signaling complex primarily expressed on effector immune cells, including CD8+ cytotoxic T cells and natural killer (NK) cells (PMID: 22391154). Unlike the high-affinity heterotrimeric receptor (IL-2Rαβγ) found on regulatory T cells (Tregs), the βγ heterodimer possesses intermediate affinity for IL-2 and is the primary driver of pro-inflammatory and anti-tumor immune responses (PMID: 31004049). In the context of oncology, this receptor is a major therapeutic target for biased IL-2 agonists designed to selectively stimulate effector cells while avoiding the immunosuppressive effects of Treg activation and the toxicity associated with IL-2Rα binding, such as vascular leak syndrome (PMID: 30610167). Upon binding its ligand, the IL-2Rβγ complex initiates the JAK/STAT, PI3K/Akt, and MAPK/ERK signaling pathways, leading to the proliferation and enhanced cytolytic activity of effector lymphocytes (UniProt: P14784, P31785). Several engineered IL-2 variants and fusion proteins, such as Nemvaleukin alfa and MDNA11, are currently in clinical development to leverage this pathway for the treatment of solid tumors (ClinicalTrials.gov). These therapies aim to overcome the limitations of recombinant human IL-2 (aldesleukin) by improving the therapeutic index and promoting sustained anti-tumor immunity.

Other names

CD122/CD132 complexIntermediate-affinity IL-2 receptorIL-2Rβ/γcIL-2Rβγ

Selective agonism of the intermediate-affinity IL-2 receptor to promote expansion of effector T cells and natural killer cells while minimizing regulatory T cell activation.