Lenalidomide activates FL patient T cells in vivo. (A) Expression of HLA-DR, CD137, PD-1, and Tim-3 by circulating CD4 and CD8 T cells measured by flow cytometry at the indicated time points. D0, first day of the first cycle of treatment (before lenalidomide intake); D7, seventh day of the first cycle (before obinutuzumab infusion); D28, first day of the second cycle (before lenalidomide intake); end, end of induction. Median values are depicted as red lines. **P < .01, ***P < .001, multiple paired samples Wilcoxon tests. (B) Correlations between PD-1 and Tim-3 expression (left panels), PD-1 and HLA-DR expression (middle panels), and PD-1 and CD137 expression (right panels) on CD4 T cells at D0 (upper row) and D7 (lower row). (C) Correlations between PD-1 and Tim-3 expression (left panels), PD-1 and HLA-DR expression (middle panels), and PD-1 and CD137 expression (right panels) on CD8 T cells at D0 (upper row) and D7 (lower row).