Fig 1.

Adalimumab-driven increase in CD4 Treg cells in PBMCs from patients with RA in vitro predicted subsequent clinical response to therapy. A, Representative FACS plot indicating the percentage of CD4⁺Foxp3⁺ Treg cells in PBMCs stimulated with adalimumab in vitro from a patient who subsequently responded and a patient who did not respond to adalimumab therapy assessed at 3 months. The right-hand panel shows that Foxp3⁺ CD4 T cells cosegregate with CD127^loCD25^hi CD4 T cells. The corresponding cumulative data of Treg-cell frequency in PBMCs from patients who responded (n = 14) or not (n = 5) to adalimumab therapy cultured with adalimumab or etanercept. B, Receiver-operating characteristic (ROC)-curve analysis of the percentage increase in Treg cells predicting clinical response (n = 19). C, Serum CRP before and after therapy in patients divided according to whether adalimumab increased Treg-cell frequency by more than 40% in the baseline sample in vitro (n = 19). CRP values for 2 responding patients who temporarily stopped their adalimumab at 6 months because of infection come from data collected between 6 and 9 months. CRP, C-reactive protein. *P < .05, ***P < .001 by paired t test.