Abstract: Objective: To study the effect of IL-24 on the differentiation and function of osteoclasts through Jak-Stat signaling pathway. Methods: The enhanced green fluorescent protein (EGFP) carried by adenovirus was used to determine the optimal multiplicity of infection (MOI). ELISA was used to detect the content of IL-24 in the medium. Real-time PCR was used to detect the related genes of Jak-Stat signaling pathway such as Jak1, Jak2, Jak3, Stat1, Stat2 and Stat3 and the expression of osteoclastic factor in RANKL-induced RAW264.7 such as NFATc1, CTSK and MMP9. Results: MOI=600 was the best condition. Content of IL-24 in the medium of transfected group was higher than that of vector group. Under the induction of RANKL, compared with vector group, the transfected group expressed higher level of Jak2 and Stat3 (P＜0.05). The addition of Stattic decreased the expression of NFATc1, CTSK and MMP9 for RAW264.7 cells transfected with IL-24 gene (P＜0.05). Conclusion: IL-24 could promote the differentiation and function of osteoclasts through Jak-Stat signaling pathway.

Key words: Osteoclast, RAW264.7, Bone resorption, Interleukin-24, Signaling transduction