Effects of hepcidin on CFU-E on colony formulation. (A) Effects of hepcidin on CFU-E colony formation at rhEpo 1.0 U/mL. Results are expressed as mean ± SEM; findings from 4 experiments are combined. No values at any hepcidin concentration differ significantly from control (no added hepcidin) or from each other (ANOVA). Mean CFU-E concentration in control clots was 610 per 105 LDMN cells. (B) Effects of 100 ng/mL hepcidin on CFU-E colony formation at reduced rhEpo concentrations are shown. Results are expressed as mean ± SEM; findings from 3 experiments are combined. Colony formation by hepcidin-exposed cells (□, broken line) is significantly less than that of unexposed cells (▪, solid line; P = .031, ANOVA). Mean CFU-E concentration in control clots was 455 per 105 LDMN cells. ACTH(1-24) (100 ng/mL) had no effect on CFU-E colony formation at rhEpo concentrations between 0.1 U/mL and 1.0 U/mL rhEpo.
