what is transferrin

Transferrin is a glycoprotein found in vertebrates that plays a crucial role in iron metabolism by binding and transporting iron through the blood plasma. It is produced in the liver and contains binding sites for two Fe³⁺ ions. When a transferrin protein loaded with iron encounters a transferrin receptor on the surface of a cell, it binds to it and is transported into the cell in a vesicle by receptor-mediated endocytosis. Transferrin is also involved in regulating the absorption of iron into the blood. A transferrin test measures the blood's ability to attach itself to iron and transport it around the body, and it is often used to assess iron deficiency or iron overload. The normal range for transferrin is 215 to 380 mg/dL, and it may also be measured using a value called total iron-binding capacity (TIBC)