FIG. 1.

CTLA-4 and PD-1 engagements inhibit T-cell activation and glucose metabolism. CD4 T cells were stimulated with immunobeads coated with the antibodies indicated, and (A) T-cell expansion, (B) IL-2 expression, (C) uptake of [³H]2-deoxyglucose, and (D) glycolysis were measured. IL-2 expression, uptake of [³H]2-deoxyglucose, and glycolysis were measured 18 h after activation. All data are representative of three independent experiments. CPM, counts per million.