IL2RB

Interleukin-2 receptor subunit beta (IL2RB), also known as CD122 or T-cell growth factor receptor β-chain, is a critical component of the high-affinity IL-2 receptor complex. It pairs with the γc subunit (IL2RG) and the α-chain (IL2RA/CD25) to mediate interleukin-2 signaling, essential for T-cell proliferation, differentiation, and immune tolerance. IL2RB activates JAK-STAT pathways (primarily JAK1/JAK3-STAT5), PI3K-AKT, and MAPK cascades upon ligand binding, regulating clonal expansion of activated T cells and natural killer (NK) cell function. Its signaling is tightly controlled through receptor internalization and SOCS protein feedback mechanisms.
Dysregulation of IL2RB is implicated in autoimmune disorders (e.g., multiple sclerosis), hematologic malignancies, and primary immunodeficiencies. Therapeutic strategies targeting this receptor include IL-2/IL-15 superagonists (e.g., bempegaldesleukin) to enhance antitumor immunity and monoclonal antibodies (e.g., basiliximab) for immunosuppression in organ transplantation. Recent clinical trials explore engineered IL-2 variants with β-selective bias to minimize vascular leak syndrome, while JAK inhibitors like tofacitinib indirectly modulate IL2RB downstream signaling in autoimmune therapies.