Figure 3.

EPO augments human Treg in vivo. (A and B) Blood samples were obtained from patients with CKD with anemia before and after 6 months of EPO therapy and from matched CKD controls without anemia (and not given EPO) at the same time points (see Supplemental Table 1 for patients’ baseline characteristics). (A) Representative flow plots and (B) data quantification of CD4⁺CD25⁺CD127^low Treg at study enrollment and after 6 months in the EPO treatment and in the control group. (C) Schematic of experimental design in NOD SCIDγc^−/− mice: 1 million CD4⁺CD25⁺FOXP3⁺ human, in vitro generated iTregs from HLA-A2^pos donors. FOXP3 expression before injection shown in (D) were injected together with 5 million PBMC from HLA-A2^– donors in NOD SCIDγc^−/− mice. Mice were treated with EPO or vehicle control for 3 days and then euthanized for analyses. (E) Representative plots of FOXP3 expression in HLA-A2^neg and HLA-A2⁺ cells and (F) percentage of splenic HLA-A2^pos cells that are FOXP3⁺ in the vehicle and EPO treatment groups. Data are from two experiments (indicated by squares and circles) with two to three mice per group in each (error bars, SEM). *P<0.05 (paired t test).