Interleukin-21 promotes osteoclastogenesis in RAW264.7 cells through the PI3K/AKT signaling pathway independently of RANKL

Cytokines play a key role in the bone destruction of rheumatoid arthritis (RA). Interleukin-21 (IL-21) promotes osteoclastogenesis in RA in a receptor activator of nuclear factor-κB ligand (RANKL)-dependent way. Whether IL-21 is capable of promoting osteoclastogenesis directly in the absence of R…