Frequency of circulating follicular helper T cells (cTfh) in patients with rheumatoid arthritis (RA). (A) The frequency of circulating CD4 + CXCR5+ T cells was not different in RA patients with active (RA-a) or inactive disease (RA-r) as compared with controls (HC). Histograms represent CXCR5 expression in cells gated for CD3 and CD4. (B) Increased frequency of circulating Tfh counterparts in RA-a or RA-r patients, defined as CD4 + CXCR5 + ICOS+ T cells. Representative dot plots demonstrate ICOS and CXCR5 expression in cells gated for CD3 and CD4. (C) Relationship between cTfh proportions and disease activity as determined by disease activity in 28 joints (DAS28) score . In A and B, box and whiskers plots represent the median, interquartile range, maximum and minimum values calculated from the 17 RA-a patients, 17 RA-r patients and 34 HC that were studied. *P <0.01 versus HC.