Figure 2. Relationships between peripheral blood Trp and its metabolites with IDO.

(A) Trp levels were significantly lower in the hemodialysis patients than in the controls. (B) Kyn levels were significantly higher in the hemodialysis patients than in the controls. (C) The Kyn/Trp ratio was significantly higher in the hemodialysis patients than in the controls. (*P<0.05, controls vs. patients). (D) The Kyn/Trp ratio did not show a correlation with the IDO MFI in PBMCs (GGH: r_s0.059, P=0.426; WHH: r_s 0.106, P=0.485). MFI: median fluorescence index; PBMCs: peripheral blood mononuclear cells.