IL-15 promotes osteoclastogenesis via the PLD pathway in rheumatoid arthritis

► We provides the first comprehensive view of the osteoclastogenic roles of PLD signaling induced by IL-15 during in vitro human osteoclastogenesis. ► IL-15 seems to play a role in the osteoclastogenesis involved in the joint destruction of RA via the PLD1 signaling pathway. ► PLD1 may be an additional multistep pathway for osteoclast differentiation that is dependent on the RANK/RANKL axis. ► Regulation of PLD expression in RA patients may provide a new treatment strategy for inhibiting the bone destruction caused by this disease.