Transferrin: Difference between revisions

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(Created page with "<section begin="clinical biochemistry" />'''Transferrin''' is a serum protein whose function is to transport iron in the blood; more specifically, each molecule of transferrin binds two Fe<sup>3+</sup> ions with high affinity. Transferrin binds to transferrin receptors on cells which require iron, after which the transferrin-transferrin receptor complex is endocytosed. The pure protein, non-iron-bound form of transferrin is called '''apoferritin'''. Transferrin is a...")
 
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As a negative acute phase protein, it'll be falsely low in case of infection or inflammation. Elevated levels of transferrin indicates long-term iron deficiency.
As a negative acute phase protein, it'll be falsely low in case of infection or inflammation. Elevated levels of transferrin indicates long-term iron deficiency.
== Soluble transferrin receptor ==
While transferrin receptor is mainly found on cell surfaces, a number of free (soluble) transferrin receptors (s-TfR) can be found in the serum as well. This is mostly from the extracellular part of the receptor of immature erythrocytes being proteolytically cleaved when the erythrocytes mature. The level of soluble transferrin receptor in the serum is proportional to the total number of transferrin receptor in tissues.
Because the soluble transferrin receptor is not an acute phase protein, its level is unaffected by the acute phase and therefore by inflammation and infection. This makes s-TfR good to evaluate iron status in patients who currently have inflammation or infection.
Elevated s-TfR levels (> 4.3 mg/L) indicate iron deficiency.


== Transferrin saturation and TIBC ==
== Transferrin saturation and TIBC ==