Serum ferritin.

(1) Brief introduction to iron metabolism and the biochemistry of ferritin. (2) Early studies of circulating ferritin. (3) Methods for measuring serum ferritin concentrations -- immunoradiometric, radioimmuno- and enzyme-linked immuno assays based on liver or spleen ferritin -- an evaluation of these techniques. (4) Serum ferritin concentrations in normal subjects -- definition of normality -- relationship between storage iron and serum ferritin concentrations -- changes during development from birth to old age -- iron deficiency -- variability of serum ferritin concentration -- evaluation of use of ferritin assay for assessment of storage iron levels. (5) Serum ferritin concentrations in disease -- hemochromatosis -- secondary iron overload -- liver damage -- infection and chronic disease -- cancer. (6) Assay of serum ferritin with antibodies to ferritins other than liver or spleen -- ferritinemia and cancer. (7) Properties of serum ferritin -- molecular weight -- iron content -- isoelectric focusing patterns -- carbohydrate content -- immunological properties. (8) Physiology of circulating ferritin -- release of ferritin from tissues -- origin of circulating ferritin -- clearance from the plasma -- iron and protein turnover. (9) Summary -- factors influencing serum ferritin concentrations and clinical use of ferritin estimations.