Fig. 4

IDO-1 inhibition and immune tolerance. a Schematic illustration of indoleamine 2,3 dioxygenase inhibition by 1-methyl-DL-tryptophan (1-MT; 100 mg/kg i.p.; 7 days) at various stages of EAE (experimental autoimmune encephalomyelitis) induction. MOG (myelin oligodendroglial protein) and PTx (pertussis toxin) injected C57BL/6 mice were treated with 1-MT prophylactically or 1-MT treatment after EAE induction at day 5 or 1-MT treatment at EAE clinical score of 1 or 1-MT treatment at EAE clinical score of 2. b FoxP3 (forkhead box protein) expression was measured in spleen of 1-MT treated EAE-induced mice (mean ± SD; ***p ≤ 0.001; **p ≤ 0.01; *p ≤ 0.05)