Invivo Anti-Mouse RANKL (CD254) Recombinant mAb

RANKL (receptor activator of nuclear factor-κB ligand), also known as TNFSF11, OPG ligand, or TRANCE, is a type II transmembrane protein of the tumor necrosis factor (TNF) superfamily whose extracellular domain can be cleaved by proteases to form a soluble form, functioning biologically as a trimer. RANKL is mainly expressed on osteoblasts, bone marrow stromal cells, activated T cells, and synovial fibroblasts. Its core function is to bind the receptor RANK on the surface of osteoclast precursors and mature osteoclasts, recruiting adaptor proteins such as TRAF6 and activating signaling pathways including NF-κB, MAPK, and NFATc1, thereby driving osteoclast differentiation, maturation, and bone-resorbing activity. This action is naturally regulated by the soluble decoy receptor osteoprotegerin (OPG), which blocks RANK signaling by competitively binding RANKL; therefore, the RANKL/OPG ratio is regarded as a key indicator of bone resorption activity. Beyond bone metabolism, RANKL also participates in immune system regulation, influencing B cell development, dendritic cell function, and T cell differentiation, and in the tumor microenvironment it promotes immune tolerance by suppressing antigen-presenting cell function, thereby supporting tumor progression. Given its dual role in bone destruction and immune suppression, RANKL has become an important therapeutic target.