A radioimmunoassay for serum ferritin.
We describe the development and evaluation of a serum ferritin radioimmunoassay, in which 125l-labeled ferritin and rabbit anti-ferritin antibody are used. Goat anti-rabbit gamma-globulin antibody, together with polyethylene glycol, is used as the separating reagent. The assay has a working range up to 500 mug of ferritin per litre, and a sample requirement of 75 mul of serum for assay at two dilutions. The assay requires 24 h. it has a sensitivity of 1.5 mug of ferritin per litre and a long-term precision (CV) of 13%. Reference intervals for a population of men were 18-330 mug/litre, with no marked age dependence, while those for a population of women older than 50 years were 18-200 mug/litre. Many apparently healthy women in the 20-50 year age group have much lower concentrations. Serum ferritin concentrations of less than 18 mug/litre are indicative of iron deficiency, defined as the absence of stainable iron in an aspirate of bone marrow.
D000328:Adult; D000367:Age Factors; D000368:Aged; D000818:Animals; D000936:Antigen-Antibody Complex; D005260:Female; D005293:Ferritins / Q000097:blood*; D006041:Goats / Q000276:immunology; D006801:Humans; D008297:Male; D008722:Methods; D008875:Middle Aged; D011817:Rabbits / Q000276:immunology; D011863:Radioimmunoassay; D012737:Sex Factors
D000936:Antigen-Antibody Complex; D005293:Ferritins