Total iron binding capacity measures the serum iron-transporting capacity of which protein?

Total iron binding capacity measures the serum iron-transporting capacity of which protein?

• A. Hemoglobin
• B. Ceruloplasmin
• C. Transferrin
• D. Ferritin

Answer: (C)

Total iron binding capacity measures the serum’s capacity to bind iron, which is provided by transferrin in the blood. Transferrin is the main iron-transport protein, carrying ferric iron to tissues such as the bone marrow for red blood cell production. Hemoglobin stores iron inside red cells, ferritin stores iron intracellularly, and ceruloplasmin is a copper-containing enzyme; none of these primarily transport iron in the bloodstream. So the test reflects how much transferrin is present and how much iron-binding capacity it has. Clinically, higher TIBC suggests more transferrin (as in iron deficiency), while lower TIBC can occur with inflammation, malnutrition, or chronic disease.

Total iron binding capacity measures the serum’s capacity to bind iron, which is provided by transferrin in the blood. Transferrin is the main iron-transport protein, carrying ferric iron to tissues such as the bone marrow for red blood cell production. Hemoglobin stores iron inside red cells, ferritin stores iron intracellularly, and ceruloplasmin is a copper-containing enzyme; none of these primarily transport iron in the bloodstream. So the test reflects how much transferrin is present and how much iron-binding capacity it has. Clinically, higher TIBC suggests more transferrin (as in iron deficiency), while lower TIBC can occur with inflammation, malnutrition, or chronic disease.