Klinische Wochenschrift

, Volume 67, Issue 10, pp 538–542 | Cite as

Occupancy of the iron-binding sites of human transferrin in sera obtained from different anatomical sites

  • W. Vogel
  • M. Herold
  • R. Margreiter
  • A. Bomford
Originalien

Summary

Transferrin is the major iron-transport protein in serum. Four molecular species (apo-, two mono-, and diferric transferrins) can be distinguished on the basis of their occupancy with iron. These species differ physicochemically and in the affinity with which they bind to the transferrin receptor. To elucidate the possible role of the four molecular species in directing the flow of iron between the major anatomical sites of iron release and utilization we have analyzed sera from eight stable multiorgan donors. The samples were obtained from veins draining the spleen, gut, and liver, and from the periphery. Employing polyacrylamide-gel electrophoresis in combination with crossed immunoelectrophoresis we were able to identify the four molecular species in all samples. Apo-transferrin was the predominant molecular species while differric transferrin was the least abundant (P<0.01). The monoferric species were dominated by the acid-stable form (iron loading on the C-terminal end of the molecule) with ratios C/N from 1.2 (splenic and posthepatic serum) to 1.5–1.6 in mesenteric or peripheral samples respectively. We conclude from our study that it is unlikely that the monoferric transferrin species play a role in directing internal iron exchange and that in accordance with most of the literature the acidstable form is preferentially loaded under physiological conditions of iron metabolism.

Key words

Iron-binding site Transferrin Tissue iron exchange Organ donors 

Abbreviations

TF

transferrin

a-TF

apo-transferrin

d-TF

diferric transferrin

1C-TF

mono-C-transferrin

1N-TF

mono-N-transferrin

PAGE

polyacrylamide-gel electrophoresis

ICU

intensive care unit

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Copyright information

© Springer-Verlag 1989

Authors and Affiliations

  • W. Vogel
    • 1
  • M. Herold
    • 1
  • R. Margreiter
    • 2
  • A. Bomford
    • 3
  1. 1.Klinik für Innere MedizinÖsterreich
  2. 2.Abteilung für Transplantationschirurgie der Universität InnsbruckÖsterreich
  3. 3.Liver UnitKing's College School of Medicine and DentistryLondon

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