Transfer | Laboratory research

Transferrin Belonging to beta-globulins, it is synthesized mainly by parenchymal cells of the liver, in small quantities - in the central nervous system, ovaries, testicles and T-helpers. The synthesis of transferrin depends on the functional state of the liver, the supply of iron in the body and the need for iron.

The main function of transferrin is to transport the absorbed iron in the intestine to its depots (liver, spleen), reticulocytes, and their precursors in the bone marrow.

Transferrin has two iron-binding loci, each of which binds to an iron ion (Fe3 +), but in the blood it is found in the form of a transferrin and a monovalent iron complex. Transferrin can also bind to other metal ions (zinc, cobalt, etc.).

Only 25-40% of the total amount of transferrin in the human body contains iron. With iron deficiency in the body and decreased levels of iron in the blood serum, the transferrin content increases. A change in these rates is one of the most important signs of iron deficiency anemia. Similar changes are observed during pregnancy and childhood, but they are less pronounced. The increase in transferrin concentration in these cases is associated with an increase in its synthesis to meet the increased needs of the body.

Compared to iron in the blood serum, transferrin levels are more stable and less dependent on sex, age, and daily changes.

In red blood cells in the spleen, liver, and bone marrow, iron released from heme is transported to the bone marrow via heme transferrin; The iron part is included in the composition of ferritin and hemosiderin.

One molecule of transferrin binds two iron atoms - Fe3 + ions, and 1 g of transferrin - about 1,25 mg of iron. In the diagnostics, the calculated value is used - saturation of transferrin (saturation) with iron (ratio of the concentration of iron in serum to the maximum ability of transferrin to bind iron, expressed as a percentage). The standard values ​​of transferrin saturation are - 20-55%. Decreased transferrin iron saturation (resulting in decreased iron concentration and increased transferrin concentration) indicates anemia due to iron deficiency. A saturation of less than 20% of transferrin is a sign of reduced iron supply to bone marrow erythrocyte precursors. With a significant increase in iron transfer of saturated transferrin in plasma, low-molecular-weight iron occurs, which can accumulate in the liver and pancreas and can cause their damage.

When should we take a transfer test?

• Differential diagnostics of anemia;
• Evaluation of iron deficiency anemia, thalassemia, sideroblastic anemia;
• Diagnosis of iron overload and hemochromatosis.

How to prepare for the test?

The test should be performed on an empty stomach.

Research material

Venous blood

Possible interpretation of the results

Transferrin concentration increases:

• Increase in transferrin content + decrease in serum iron (iron deficiency anemia);
• Increase in transferrin and serum iron content (when taking oral contraceptives);
• Pregnancy (increased synthesis);
• Childhood (enhanced synthesis).

Transferrin concentration decreases:

• Decreased transferrin content + increase in iron concentration (idiopathic hemochromatosis, hypoplastic, hemolytic, megaloblastic anemia, iron deficiency syndrome);
• Decreased transferrin content + Decreased iron concentration (protein starvation, acute and chronic infections, cirrhosis of the liver, surgical interventions, tumors, etc.);
• Congenital atransferinemia;
• Anemia in chronic diseases;
• Nephrotic syndrome;
• Acute liver disease;
• Inadequate intake of iron supplements (increasing the dose).

Resources

https://spravochnik.synevo.ua/ru/diagnostica-anemii/transferrin.html