CTLA4 and rheumatoid arthritis: Moreover, ROC curve analysis revealed that, at baseline, having CD4posCD25posFoxP3pos cell rate ≥ 6.0% [(AUC) 95% CI: 0.66 (0.57–0.74), p = 0.001] (Supplementary Fig. 2) significantly identifies naïve to bDMARDs early RA patients more likely to achieve DAS remission under CTLA4-Ig treatment at 6 months (83.3%) compared to RA patients with baseline CD4posCD25posFoxP3pos cells < 6.0% [16.7%, p = 0.021 (χ2 test), OR (95% Cis): 25.00 (1.00 – 336.81)] (Fig. 4D).