As Mitf upregulation was the most prominent feature of TRIM-induced transcriptomic rewiring in synovial macrophages in arthritis, and already detectable in splenic monocytes/OCPs from trained mice, we next assessed the function of MITF in mediating innate immune training of inflammatory osteoclasto-genesis and exacerbation of inflammatory bone loss. Here, MITF is linked to arthritic joint disease.