Erythrophagocytosis in the human bone marrow as disclosed by iliacal bone biopsies

Erythrophagocytosis in human bone marrow has been studied in selected series of iliacal bone biopsies embedded in methacrylate or epoxy resin. Using established light microscopic criteria for recognition of the early digestive erythrophagic vacuole, intense erythrophagic activity was encountered in a series of 5 patients with haemolytic disease. A series of 32 biopsies, selected to represent 'normal' bone marrow, demonstrated low or modest erythrophagic activity in all cases. The findings are in accordance with previous demonstration of erythrophagocytosis in human bone marrow at autopsy and point to the bone marrow as the main site for destruction of aged red cells in the healthy human organism.