Taken together, the present study reveals a novel mechanism by which WTAP regulates macrophage polarization via m6A modification of RA-FLS-derived exosomal circ-CBLB, therefore providing a new perspective for RA pathogenesis and underlining the WTAP-circ-CBLB axis as a potential target for the therapeutic strategies of RA. The gene discussed is WTAP; the disease is rheumatoid arthritis.