Alix (Apoptosis-linked gene 2 interacting protein X), ubiquitously expressed and concentrated in phagosomes and EXOs, is involved in virus entry, neurodegeneration, tumor-mediated immunosuppression and more, but rarely studied in the context of arthritis.37–39 In our preliminary experiment, we found that the expression of Alix was downregulated in TMJOA synovial tissues (data not shown). Here, PDCD6IP is linked to arthritic joint disease.