Figure 3. The CCR7^loPD-1^hi subset of circulating Tfh cells correlates with disease activity of pSS and represents glandular inflammation of pSS. (A) Gating strategies for CCR7^loPD-1^hi and CCR7^hiPD-1^lo subsets from circulating Tfh and Tfr cells. (B) Circulating CCR7^loPD-1^hi Tfh cells tended to increase in pSS patients (n=18) as compared to HCs (n=14), although circulating Tfh cells showed similar frequencies between pSS patients and HCs. (C) The CCR7^loPD-1^hi subset of circulating Tfh cells was markedly increased in pSS patients with FS >3 versus HCs (1-way ANOVA with post-hoc Bonferroni test). (D) Frequencies of circulating CCR7^loPD-1^hi Tfr cells are similar between pSS patients (n=18) and HCs (n=14). (E) Correlation plot of circulating Tfh and Tfr cells and their subsets with circulating plasmablast and plasma cell populations, serum anti-SSA/Ro Ab titers, serum RF titers, serum IgG levels, serum IL-21 levels, and the ESSDAI. (F) Correlation of circulating CCR7^loPD-1^hi Tfh cells with ESSDAI scores (n=18). (G) Correlation of circulating CCR7^loPD-1^hi Tfh cells with circulating plasma cells (n=32). Bars indicate the means±SEMs.

^*p<0.05; ^**p<0.01.