B-cell maturation antigen (BCMA)
B-cell maturation antigen (BCMA) is a protein that resides on the surface of mature B lymphocytes, which are crucial components of the immune system. This protein plays a significant role in regulating cell growth and survival, making it a focal point of research, particularly in relation to multiple myeloma, a type of blood cancer. In multiple myeloma, cancerous plasma cells proliferate uncontrollably, leading to severe health complications. BCMA is notably present on both healthy and malignant B cells, and its increased presence in the blood of multiple myeloma patients suggests a link to the disease's progression.
Researchers are exploring innovative therapies that leverage BCMA's unique expression pattern. One promising approach involves genetically modifying T cells to specifically target and attack B cells marked by BCMA, thereby aiming to minimize harm to healthy cells while effectively combating cancerous ones. This targeted strategy reflects a broader trend in cancer treatment, focusing on precision medicine that aligns with individual cellular markers. As investigations into BCMA continue, it holds potential not only for understanding multiple myeloma but also for developing effective treatments that could improve patient outcomes.
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B-cell maturation antigen (BCMA)
A B-cell maturation antigen (BCMA) is a protein found on mature types of white blood cells called B lymphocytes, or B cells. The protein sends signals within the cell that help with cell growth, survival, and other processes. Doctors are interested in BCMA because of its potential use in combatting a specific form of blood cancer called multiple myeloma. Researchers are looking into ways to use the BCMA found in cancerous cells to signal the body’s immune system to target those cells.
Overview
Blood cells perform a number of different tasks in the human body. Red blood cells contain a protein called hemoglobin that carries oxygen from the lungs throughout the body and removes carbon dioxide waste to be expelled by the lungs. White blood cells are a part of body’s immune system and help defend against foreign invaders such as viruses or bacteria. Lymphocytes are one of five types of white blood cells. They originate in the bone marrow—the soft inside of the bones—and fan out through the body by a network of tissues and organs. When lymphocytes mature, they will become specialized into one of two types. T lymphocytes, or T cells, primarily act as hunters that identify and kill the invaders. B lymphocytes, or B cells, produce proteins called antibodies that neutralize the invading organism or “mark” it for destruction by T cells.
Lymphocytes are programmed to identify a type of molecule on the surface of an invader or infected cell called an antigen. Both T cells and B cells have receptors on their surfaces designed to respond to a specific antigen. That way, the cells know which invader to target. When a B cell detects its target antigen it binds to that specific object. The B cells then mature and turn into plasma cells—white blood cells that produce large amounts of antibodies. The antibodies have the same antigen receptors as their parent cell and target the same object.
If the plasma cells become cancerous, they continue to grow in the body unchecked. Over time, the cancerous plasma cells will multiply to crowd out healthy cells. This condition is known as multiple myeloma. The cancerous cells not only prevent healthy cells from making infection-fighting antibodies, but they also produce abnormal antibodies that can severely damage the kidneys.
Scientists have discovered that BCMA is present on the surface of mature B cells, plasma cells, and cancerous plasma and B cells. Because one of the functions of BCMA is to regulate cell growth, an increase in its amount may spur the growth of cancerous cells, while a decrease may limit that growth. Researchers have found that BCMA is common in the blood of patients with multiple myeloma.
The fact that BCMA is exclusively found on B cells and nowhere else in the body has led to several promising treatment strategies in the fight against multiple myeloma. Researchers have developed ways to genetically reprogram T cells to hunt down and target cells with BCMA. In this way, the T cells will only attack cells with the BCMA marker and leave healthy cells alone.
Bibliography
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