The transferrine or sidérophiline is a globuline beta, TOKEN ENTRY 76  000, synthesized by the Liver; it consists of only one polypeptide chain carrying 2 sites of collecting of iron, at a rate of 2 atoms of Fer per molecule of transferrine. The function of the transferrine is the transport of the iron of the intestine towards the hepatic reserves and the Réticulocyte S.

At the normal subject, the totality of serum iron, 100 micrograms (microgr.) by 100 ml of serum, is fixed on the transferrine. This quantity of iron represents only one third of the transport capacity of protein. The transferrine is present in the serum of a normal subject at a concentration from 200 to 300 Mg by 100 ml and the quantity of iron which it can fix at full saturation is about 360 microgr. The variations of concentration of the transferrine are rather parallel to those of the Albumine. Like the latter, the transferrine decreases in the event of hepatic Insuffisance, during the acute reactions Inflammatoire S and in the nephrotic Syndrome.

The fluctuations of the concentration of the serum transferrine and its iron saturation, are closely related to the part which she plays in the metabolism of iron.

a) In all the states characterized by a deficit of the iron reserves, state of requirement out of iron, the concentration of the transferrine rises in the serum, its iron saturation decreases, and serum iron is low. This triad is found in ferriprives anemias, the continuations of a hemorrhage, the last quarters of the pregnancy, the first years of the life where the growth requires much iron.

b) On the other hand, in all the states where the organization where the organization has a excess of iron of reserve , the rate of transferrine tends to drop; its iron saturation is almost complete, and consequently, the rate of serum iron is raised, about 250 to 300 microgr. by 100 ml of serum. These characteristics are found in the haemolytic syndromes, the excess of transfusions, anemias refractory with iron or Sidéro-achrestique S and the idiopathic Hémochromatose. In this last affection, the intestinal resorption of iron is excessive and iron is stored in the form of ferritin in the liver and the Reticulo-endothelial Système (S.R.E.).

VN of the transferrine = 200 - 300 mg/100 ml. Saturation of the transferrine = 30%.