Figure 2.

IDO1 expression inhibited the stimulatory capacity of mature DCs. (a) DCs matured with the cytokine cocktail without PGE₂ (expressing low IDO1) or complete of PGE₂ (expressing high IDO1) were used as stimulator of either allogeneic or autologous CD3⁺ T cells. For the stimulation of autologous CD3⁺ T cells, DCs were previously pulsed with tetanus toxin. ^* P < 0.05, ^** P < 0.01. Both in the allogeneic (b) and in the autologous (c) setting, the assay was performed either in presence or in absence of the IDO1-specific inhibitor 1-MT-L. The results are expressed as the mean of fold increase of 5 independent experiments ± SEM. ^* P < 0.05, ^** P < 0.01 versus medium alone.