Reticuloendothelial cell in the bone marrow and its relationship to iron metabolism.

Abstract

Qualitative and quantitative observations of stainable iron in the bone marrow reticulum cell and in the sideroblast were performed in various hematological disorders of human subjects. Histological and metabolic studies of iron in reticulum cells of the liver, spleen and bone marrow after the administration of colloidal iron and Mohr's salt were carried out in rabbits under various experimental conditions. 1) Hemosiderin granules in the bone marrow reticulum cell varied in various hematological disorders, not only in their amount, but also in their form and nature. 2) There was a moderate correlation between the number of iron granules in the bone marrow reticulum cell and in sideroblasts. Both of them were well correlated to the ability of erythropoiesis. 3) In animal experiments, stainable iron in the reticulum cell of the liver, spleen and bone marrow were markedly increased 4 hours after the injection of colloidal iron. After that, iron in the cell was re-distributed to other tissues according to the various experimental conditions. When a large dose of Mohr's salt was injected, iron was taken chiefly by the parenchymal cell of the liver, and then it was eluted to plasma and saturated transferrin for several hours. Kinetics of hemosiderin iron in the reticulum cell was studied under various experimental conditions. 4) From the study of the hemosiderin turnover in reticulum cells, it was suggested that there might be a functional difference between the reticulum cell of the spleen and of the bone marrow. 5) The frequency of phagocytosis of erythroblasts and erythrocytes in the bone marrow reticulum cell was studied in clinical cases and in experimental animals, and its significance was discussed.