Red cell ghost-entrapped deferoxamine as a model clinical targeted delivery system for iron chelators and other compounds.

In iron overload resulting from repeated blood transfusion, phagocytic reticuloendothelial cells are the primary and major sites of iron accumulation. Removal of this iron by the iron chelator deferoxamine can be enhanced by targeted delivery of this agent to reticuloendothelial cells. We have used resealed erythrocyte ghosts as a model system for delivery of deferoxamine to reticuloendothelial cells and have demonstrated a several-fold enhancement of urine iron excretion in children and adults with congenital or acquired iron-loading anemias. Although presently not cost-effective, this approach provides a useful, practical and safe model for [1] iron chelator targeting to reticuloendothelial cells, and [2] the clinical use of resealed erythrocyte ghosts for targeting pharmacologic agents to reticuloendothelial cells.