Transferriiniä

Transferriiniä, known in English as transferrin, is a metalloprotein found in the blood plasma of vertebrates. Its primary function is to transport iron from the digestive system and storage sites to the bone marrow, where red blood cells are produced. Transferrin binds to iron in a reversible manner, picking it up in the duodenum and releasing it in the bone marrow. It can bind to two iron atoms, typically in the ferric (Fe³⁺) state.

The concentration of transferrin in the blood is an important indicator of iron metabolism and can be used to diagnose various conditions, including iron deficiency anemia and hemochromatosis. In iron deficiency anemia, transferrin levels are typically elevated as the body attempts to maximize iron uptake. Conversely, in conditions of iron overload, transferrin saturation, which represents the percentage of transferrin binding sites occupied by iron, may be high.

Besides iron, transferrin can also bind to other metal ions, albeit with much lower affinity. It plays a role in regulating the bioavailability of iron, ensuring that sufficient iron is available for essential cellular functions while also preventing the accumulation of free iron, which can be toxic due to its pro-oxidant properties. Transferrin is synthesized primarily in the liver.