Changes in ferritin, nonheme Fe, and mRNA levels of FPN1, HO-1, Nramp1, and DMT1 after erythrophagocytosis (EP) by J774 macrophages. J774 cells (approximately 4 × 10⁶) were incubated in the presence of 100 × 10⁶ opsonized rat erythrocytes (EIgG) for 2 hours. Noningested erythrocytes were lysed and removed, and incubation was continued for the times shown. (A) Western analysis of ferritin (LFt indicates ferritin light chain; HFt, ferritin heavy chain). The position of murine LFt above that of HFt was determined previously in studies of MEL cells stably transfected with HFt.⁴⁰  (B) Nonheme Fe (▴), and LFt (▪) levels plotted as a function of time after EP. (C) Northern analysis of FPN1, HO-1, Nramp1, and DMT1. (D) mRNA levels of FPN1 (♦), HO-1 (▪), Nramp1 (▴), DMT1 (○), all normalized to β-actin, plotted as a function of time after EP. Results shown in panels A-B are from a single experiment and confirm previously published data.^7,41-43,45  Results shown in panels C-D are representative of at least 2 similar experiments.