The association between peripheral blood circulating follicular helper T cells and antibody-secreting B cells in patients with ankylosing spondylitis

Abstract

Objective To investigate the relationship between peripheral blood circulating follicular helper T cells and antibody-secreting B cells in patients with ankylosing spondylitis (AS). The role of circulating follicular helper T cells and antibody-secreting B cells in the pathogenesis of AS were explored. Methods Flow cytometry was used to detect the levels of peripheral blood CD4+CXCR5+ T(cTfh), CD4+CXCR5+ PD-1+ T, CD4+ CXCR5+ ICOS+ T, CD19+ B, CD19+ CD38+ B cells in 59 patients with AS (including 36 cases of active AS patients and 23 cases of inactive AS patients). In addition, twenty healthy persons were selected as the controls. Data analysis were performed by independent-sample t test, One way ANOVA analysis, Pearson's and Spearman's correlation test. Results The percentages of cTfh[(26.8±10.4)%], CD4+CXCR5+ PD-1+ T [(12.1±14.0)%], CD4+CXCR5+ICOS+ T [(13.6±9.5)%], CD19+CD38+ B [(80.7±13.0)%] in the peripheral blood of AS group were significantly higher than healthy controls [(15.6±4.5)%, (6.4±2.4)%, (9.4±4.5)%, (68.2±13.0)%] (t=6.663, P<0.01; t=2.999, P<0.01; t=2.573, P<0.05; t=2.712, P<0.01) . The percentages of cTfh in the active AS group [(30.2±11.0)%] were significantly higher than those in the inactive AS group [(21.4±6.5)%] and HC (t=3.444, P<0.01; t=7.004, P<0.01). The percentage of CD19+ CD38+ B [(85.1±10.0)%] in the peripheral blood of active AS group was significantly higher than that of the inactive AS group [(73.8±14.2)%] and HC (t=3.561, P<0.01; t=5.410, P<0.01). The relationship between Bath AS disease activity index (BASDAI) and the percentage of cTfh, CD19+ CD38+ B was a positive correlation (r=0.442, P<0.01; r=0.405, P=0.001), and significant positive correlation was observed between the percentages of cTfh and CD19+CD38+ B cells (r=0.420, P=0.001). Conclusion CD4+CXCR5+·cTfh cells are significantly increased in peripheral blood in AS patients with aberrant CD19+ CD38+ antibody-secreting B cells, suggesting that cTfh and CD19+ CD38+ antibody-secreting B cells may play an important role in the pathogenesis of AS. Key words: T-lymphocytes, helper-inducer; B lymphocytes; Spondylitis, ankylosing