IDO1 and CTLA-4 blockade induces liver injury in <i>PD-1</i>^<i>-/-</i> mice.

PD-1-/- mice were treated with 9D9, epacadostat (A, C panels are 300 mg/kg BID only, B includes 300 and 600 mg/kg BID), or in combination for 2 or 6 weeks. (A) Representative H&E images and (B) quantification of single cell necrosis. (C) GLDH levels through 6 weeks. Arrows indicate immune cell accumulation. Arrowheads indicate a necrotic cell. Scale bar = 150 μm. All data (n = 6 per group) are reported as mean ± SEM. Necrosis data was analyzed with a Kruskal-Wallis test and Dunn’s multiple comparisons test. GLDH data was analyzed with a repeated measures two-way ANOVA and Tukey’s multiple comparisons test. aP bP cP < 0.05 epacadostat vs vehicle, 9D9.