Serum and Liver Isoferritin Differences: Evidence That Serum Ferritin May Be Underestimated in Hyperferritinemia

Abstract

Summary

We have used gel filtration chro-matography to compare relative antibody affinities of liver ferritin and serum ferritin from patients with idiopathic hemochroma-tosis and other causes of hyperferritinemia such as liver disease, transfusional iron overload, and cancer. When equal amounts of either liver or serum ferritin were mixed with ¹²⁵I-labeled antiferritin antibody then eluted through an agarose column, we obtained higher antigen-antibody complex recovery with the serum ferritin than liver ferritin. This was more marked in patients with untreated, idiopathic hemochromatosis. Our findings provide additional evidence of different reactivity between serum isoferritins and an antibody prepared against organ-specific ferritin. Further, this suggests that the immuno-radiometric assay may underestimate serum ferritin concentration in patients with high ferritin values.