At post hoc analysis, in the PB from patients with JIA, the percentage of CCR7+ cells in the CD4+CD45RO+ subpopulation (median 65.5%, range 50–90%) was significantly lower than in PB from controls (median 76%, range 73–89%, P = 0.03, Mann–Whitney U-test). Here, CCR7 is linked to juvenile idiopathic arthritis.