A Solid-Phase Enzyme Immunoassayfor Serum Ferritin

We describe an enzyme immunoassay for human serum ferritin in which antibody adsorbed on polystyrene tubes is used. Adsorbed gamma-globulins against human ferritin were first allowed to react with ferritin and a second anti-ferritin antibody, labeled with alkaline phosphatase, was added. The amount of bound enzyme/antibody conjugate was proportional to the ferritin titer in the assay. This method offers stable reagents that can be kept for many months at 4 #{176}C.The average values for ferritin in normal men and women were, respectively, 58 and 43 pg/liter. The lowest detectable concentration was 5 tg/liter. Ferritin, in its various forms, plays a very important role in iron storage and metabolism (1). It is present in various tissues but especially in liver, spleen, and bone marrow (1). The presence of ferritin in certain tumors and the increased tite