Whilst CIA was applied to evaluate the efficacy of EVs therapies as a model of RA, demonstrating strong immunomodulatory effects with unknown mechanism [19] or indicating T-lymphocyte mechanisms underpin therapeutic outcomes [39], the AIA model remains appropriate for examining immunomodulatory molecular changes evoked through the action of EVs on CD4+ T cells [38]. Here, CD4 is linked to rheumatoid arthritis.