Introduction:
Blood is a specialized, complex body fluid that performs various body functions such as transporting oxygen and essential nutrients to the lungs and tissues, forming blood clots to prevent excess blood loss, carrying cells that fight infection, removing the waste products by bringing them to the kidneys and liver, which filter and clean the blood and regulate the body temperature. The blood contains a mixture of about 55 percent plasma (liquid part) and 45 percent blood cells (solid part). The process of formation of blood or hematopoiesis occurs mainly in the bone marrow. The process is facilitated by transferrin, which plays an important role in transporting iron, an essential component for blood formation. This article briefly explains the role of transferrin in blood formation.
What Is Transferrin?
Transferrin is a glycoprotein that helps the blood carry iron to different parts of the body, including the spleen, liver, and bone marrow. It acts as a biochemical marker to detect the iron level of the body.
Transferrin divides into subgroups:
1. Serum Transferrin: Serum transferrin is produced by liver cells and is found in the serum, CSF, and semen.
2. Lactotransferrin: Mucosal epithelial cells produce this type of transferrin and are seen in bodily secretions such as milk. Lactotransferrin has antioxidants, antimicrobial and anti-inflammatory properties.
3. Melanotransferrin: It is a type of transferrin primarly found melanocytes. It plays an important role in regulating iron metabolim in melanocytes.
What Is the Role of Transferrin in Blood Formation?
Blood is composed of various cells, such as red blood cells, white blood cells, and platelets. Blood formation does not occur in blood vessels; it occurs in the bone marrow, a spongy tissue inside the bones. This spongy tissue has young parent cells known as stem cells. These stem cells that generate have the ability to develop into red blood cells, white blood cells, and platelets. Blood cells leave the bone marrow and enter the bloodstream when they are completely developed and functional. The blood formation is a continuous process. The bone marrow requires a constant supply of iron for red blood cell formation through its involvement in the synthesis of hemoglobin and the maturation of red blood cells. In order to provide sufficient iron, the carrier protein transferrin is needed.
This protein, transferrin, has the ability to bind with the iron in the blood and transport it to various tissues, such as the liver and spleen, including bone marrow, where the formation of red blood cells takes place. Iron is a key component for the formation of red blood cells through its role in the synthesis of hemoglobin, the protein that is responsible for transporting oxygen from the lungs to cells throughout the body. The bone marrow requires a constant supply of iron to support the synthesis of hemoglobin and the maturation of red blood cells during erythropoiesis. Transferrin serves as a primary iron carrier in the blood. Having enough transferrin levels can effectively use the iron from the diet one eats. Transferrin levels increase with iron deficiency. When iron is low, the body tries to compensate by making more transferrin to increase the availability of iron. On the other hand, when there is iron overload, transferrin levels will decrease.
How Does Transferrin Transport Iron to the Bone Marrow for Blood Formation?
Iron plays a key role in the formation of red blood cells in the bone marrow. All the iron in plasma is bound to transferrin. Allowing the safe transport of iron to the cells. After iron and transferrin are bonded, transferrin transports the iron to the bone marrow, where it is used to produce hemoglobin and parts of erythrocytes. Circulating transferrin exists in two forms; it can be devoid of iron, called apo-transferrin, or fully loaded with iron, called halo-transferrin, which is ready for transport to the bone marrow, where red blood cell formation takes place. The bone marrow contains specialized cells known as erythroblast cells, which arise from stem cells and play a key role in red blood cell formation. These cells have two receptors: transferrin receptor 1 (TFR1) and transferrin receptor type 2 (TFR2), which specifically binds to halo-transferrin (fully loaded with iron). In this way, the iron enters the bone marrow, which helps in red cell formation. A malfunction of any of these receptors can impair the process of red cell formation, which leads to defective red blood cells.
What Is the Normal Range of Transferrin?
The normal reference range for transferrin is 204-360 mg/dL. The level of transferrin in the blood suggests the amount of iron in the human body. Transferrin levels above this range indicate low levels of iron, suggestive of iron-deficiency anemia, which affects red blood cell formation. Transferrin levels below the normal range can impact the transport of iron to various tissues since transferrin is the main carrier of iron. This leads to iron deficiency anemia that affects the production of red blood cell formation.
What Are the Causes of Low Transferrin Levels?
Decreased transferrin values are found in the following conditions:
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Long-Term Iron Deficiency Anemia: Long-term iron deficiency anemia can lead to low transferrin levels.
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Liver Damage: Liver damage or dysfunction can lead to decreased production of transferrin.
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Kidney Injury or Disease: Kidney injury or disease can cause loss of transferrin in urine, which leads to decreased levels of transferrin in blood.
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Long-Term Infections: Prolonged infections can alter the transferrin levels in the blood.
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Uremia: A condition that causes the buildup of toxins in blood due to kidney dysfunction.
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Atransferrinemia: Atransferrinemia is a genetic mutation resulting in transferrin deficiency, which leads to excessive accumulation of iron deposits in the heart and liver, which can lead to heart and liver failure.)
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Malignancy (Cancer): Some types of cancer affect liver or bone marrow which disrupts the normal production of transferrin.
Conclusion:
Transferrin is a glycoprotein that facilitates the transport of iron to various bodily areas. It also acts as a biochemical marker to detect the iron level of the body. The ability of transferrin to bind iron and deliver it to various tissues, including the liver, spleen, and bone marrow, transferrin also ensures a constant supply of iron necessary for hemoglobin synthesis and red blood cell maturation. Understanding the role of transferrin in blood formation highlights its significance in maintaining optimal blood health. It highlights its potential as a diagnostic marker for conditions such as iron-deficiency anemia.
