IDO1 inhibition reverses T-cell suppression mediated by IDO-expressing HeLa cells or DCs. Appropriate numbers of HeLa cells, or dendritic cells (DCs) and T cells, were mixed in 96-well plates, and treated with 100 U/mL IL-2 and 100 ng/mL anti-CD3 antibody, as well as 50 ng/mL IFN-γ and 5 μg/mL LPS (only in the DC-T coculture) and various concentrations of INCB024360 as indicated for 2 days. Cell proliferation was measured using the BrdU incorporation cell proliferation ELISA kit. Representative data of 3 independent experiments are presented. Data are from HeLa-T coculture (A) and DC-T coculture (B).