Iron availability and complex stability of iron hydroxyethyl starch and iron dextran a comparative in vitro study with liver cells and macrophages.

BACKGROUND Intravenous iron (IVI) therapy is required in patients with end-stage renal disease (ESRD) under chronic haemodialysis (HD). In this in vitro study we investigated the availability and stability of iron hydroxyethyl starch (iron-Hes) compounds in THP-1 cells (macrophage phenotype) and liver cells (HepG2 cells) and compared it with the well-known iron dextran. METHODS The uptake and release of these iron formulations by THP-1 cells (macrophage phenotype) and HepG2 cells were investigated with atomic absorption spectrometry (AAS). Ferritin was measured by ELISA. HepG2 cells were used to investigate effects of IVI on the intracellular labile iron pool (LIP), which was measured by using the fluorescent calcein assay. The amount of redox-active iron within the iron formulations was assayed using dichlorofluorescein as fluorescent probe. RESULTS All iron preparations were taken up, stored in ferritin and released again by macrophages and HepG2-cells. This study shows that the availability and stability of iron-HES formulations in vitro are comparable with the well-known iron dextran compounds. CONCLUSIONS Our results indicate that these new iron formulations have a good stability and availability in vitro and are comparable with the well-known iron dextran complexes.