Figure 1

Increase of Tregs with intermediate Foxp3 expression in inflamed PsA joints. Flow cytometry analysis of Foxp3 expression by CD4 + CD25 + CD127^lo T cells derived from peripheral blood of HC (n = 13), psoriasis patients (n = 21) and PsA patients (n = 20), and from synovial fluid of PsA patients (n = 6). Bar graphs: symbols represent individual subjects; bars show median with interquartile range; *P value < 0.05 (PsA synovial fluid only compared with PsA peripheral blood). (A) Gating strategy for CD4 + CD25 + CD127^loFoxp3 + Tregs. We differentiated between Tregs with intermediate and high expression of Foxp3 (Foxp3^int and Foxp3^hi, respectively). Percentages in dot plots represent median of peripheral blood-derived Tregs in PsA. (B) Foxp3 expression by CD4 + CD25 + CD127^lo T cells. (C) Proportion of Foxp3^int and Foxp3^hi Tregs of CD4 + CD25 + CD127^lo T cells. Foxp3^int/^hi: forkhead box P3 expression intermediate / high; FSC-A: forward scatter area; FSC-H: forward scatter height; HC: healthy control; MFI: median fluorescent intensity; PsA: psoriatic arthritis; PsO: psoriasis; SSC-A: sideward scatter area; Treg: T regulatory cell.