ANTIGEN-ANTIBODY
Autoimmune hemolytic anemia is a disease in which red blood cells (RBCs) are destroyed and removed from the
bloodstream of an organism before each RBC’s normal lifespan of around 120 days is complete. When RBCs die, one of
the many functions of the bone marrow is to produce enough RBCs to replace these lost RBCs, but in the case of
hemolytic anemia the bone marrow fails to create RBCs at a rate fast enough to replace its newly lost RBCs. RBCs are
also commonly referred to as erythrocytes, and they are all made in a spongy-like tissue inside bones known as red bone
marrow. Stem cells, responsible for the creation of all erythrocytes, are thus likewise located in red bone marrow. The
mitosis of stem cells in red bone marrow is stimulated by the hormone erythropoietin (EPO), which is produced in the
kidney and travels through various blood vessels before it reaches bone marrow. EPO binds to protein receptors on the
stem cells in the bone marrow and facilitates the mitosis and therefore creation of these erythrocytes.
The majority of erythrocytes contains antigens, or expressed protein substances, that can be found on the surface
of those erythrocytes. Antigens are recognized by the immune system as a foreign “intruders” and therefore their presence
on the surface of an erythrocyte triggers the production of a force to remove them. Antibodies are signal proteins secreted
by B-lymphocytes circulating in blood plasma, and they are used to identify, neutralize or remove substances, that
originated from within an organism or the external environment, with the potential to harm erythrocytes. Antibodies
“flag” antigens that are “foreign” and take direct action to remove these antigens. By binding to a “bad” antigen on a
cell’s surface, antibodies produced by that cell send a signal to that cell’s T-cells. This signal initiates the removal of the
“foreign antigen” by T-cells with specifically shaped receptors that, when fit together with the “foreign” antigen, release
chemicals that effectively destroy the antigen. While the majority of the antigens normally present on erythrocytes,
necessary for human survival, are not identified as foreign by an organism’s antibodies, those who are “anemic” have
antibodies that incorrectly label these erythrocytes as dangerous, and T-cells consequently remove healthy erythrocytes.
Erythrocytes contain the element Iron, which is a component of an oxygen-rich protein referred to as hemoglobin
in the cell. Hemoglobin is a protein that allows erythrocytes to bind and transport chemicals such as oxygen from the
pulmonary capillaries of the lungs through the bloodstream to other cells. Hemoglobin is known for its ability to transfer
oxygen to oxygen-deficient cells. Therefore, the more erythrocytes containing hemoglobin present in the bloodstream, the
greater oxygen carrying capacity of these cells. To make the protein hemoglobin, a cell needs amino acids, enzymes and
sufficient Iron from the digestive system.
Autoimmune diseases such as hemolytic anemia cause an abnormal immune response: the removal of non-foreign
erythrocytes from the blood. Human beings are considered “anemic” if the hemoglobin in their cells decreases,
diminishing the carrying capacity of oxygen to their cells. Hematocrit, the volume percentage of erythrocytes in the blood,
consequently decreases as antibodies in each cell “flag” healthy antigens as “foreign,” leading that cell’s T-cells to destroy
too many perfectly normal cells. This decrease in oxygen availability, due to reduced the reduced number of healthy cells
carrying hemoglobin, is sensed by kidney cells, which then secrete more EPO causing the blood to become thicker due to
an increase in erythrocytes. While there is now an increase in the percentage of hematocrit of the blood, the thickness
from an increase in erythrocytes creates an environment in the blood that is overly viscous. This viscosity causes
erythrocytes to experience hemolysis, in which they rupture and liberate their hemoglobin into surrounding extracellular
fluids. The rupturing of erythrocytes also causes an insufficient plasma concentration and inevitability decreased oxygen
concentration of the blood, causing inadequate oxygenation of the blood, otherwise referred to as hypoxia.
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HEMOLYSIS: the breaking down of red blood cells with liberation of hemoglobin. is the rupturing of erythrocytes (red blood
cells) and the release of their contents (cytoplasm) into surrounding fluid
Hemolytic anemia occurs when the bone marrow is unable to replace the red blood cells that are being destroyed.
Hypoxia: inadequate oxygenation of the blood, therefore deficiency in the amount of 02 delivered to body tissues,
Hypoxia (also known as hypoxiation) is a condition in which the body or a region of the body is deprived of adequate oxygen supply
Hypoxia can result from a failure at any stage in the delivery of oxygen to cells. This can include decreased partial pressures of oxygen,
problems with diffusion of oxygen in the lungs, insufficient available hemoglobin, problems with blood flow to the end tissue, and
problems with breathing rhythm.