Transferrins are iron-binding blood plasma glycoproteins isolated from serum. It can control the level of free iron in biological fluids by binding to a specific cell surface receptor to deliver iron atoms via receptor-mediated endocytosis. Transferrin can cause the transport and uptake of iron from cell culture medium to cells, thus to supply iron atomswhich is required for the cellular uptake of oxygen. Holo transferrin is iron saturated transferrin. After releasing iron, it will become apo-transferrin, the iron-deficient transferrin.
