In 1937, a French scientist, Laufberger,1 isolated from horse spleen a new crystalline protein that contained as much as 23% by dry weight of iron. This substance was given the name ferritin. Subsequent studies have shown that this unique protein serves several important functions in the animal organism. One of these is that of iron storage, particularly in the liver. After the injection of radioactive iron intravenously into dogs, as much as 80% of the administered iron can be recovered in the form of ferritin in the liver.2 Iron from liver ferritin can then be mobilized as needed for hemoglobin synthesis.
A second alleged function of ferritin is related to the absorption of iron by the mucosa of the intestinal tract. According to the view of Granick,3 the mucosal cells of the intestine contain a protein, apoferritin, which combines with the iron released from foods as the