BANK1 was expressed in naïve DBA1/J mice at much higher levels in lymphoid nodules, which primarily comprise B cells, than in CIA mice (14 days and 35 days after immunization), particularly in mice with acute exacerbation of arthritis (35 days after immunization) (Fig. 1d, original magnification × 20 and × 40). Here, BANK1 is linked to arthritic joint disease.