In contrast, only frequencies of IDO+/IL-10+/M-/PMN-MDSCs in the PB but not PF/TT were significantly greater than in HD (p < 0.05, p < 0.01, and p < 0.01, p < 0.001; Figures 3B,C, respectively); we failed to observe similar changes in the abundance of TGF-β+M-/PMN-MDSCs (Figure 3D). The gene discussed is IDO1; the disease is Huntington disease.