The plasma cells are an important part of the human immune system and are used to form antibodies. Their special features are the large cytoplasm and the eccentrically located cell nucleus. The round to oval plasma cell reaches a size of 10 to 18 microns. Their life span is between a few days and several months.
Plasma cells arise from the B cells through differentiation and are mainly found in the spleen, the lymph nodes and the intestinal mucosa. The lifespan of a plasma cell varies from a few days or weeks to very long-lived plasma cells.
The task of the plasma cells
A plasma cell is a special subtype of B lymphocytes. Their main task is the formation of antibodies, which have an important protective function on the human body.
The antibodies consist of special proteins and can be found in the blood and other body fluids. Together with other complex defense systems, they form the immune system. Antibodies protect the human organism
- bacteria, fungi and viruses,
- tumor cells,
- animal toxins as well
- numerous natural and artificial substances.
Plasma cells, important part of the immune system
When B cells encounter T cells within the lymph nodes that recognize the antigen, some form plasma cells. The other part develops into memory B cells. When the organism encounters the antigen again, they react faster. In contrast to B cells, plasma cells no longer divide. They migrate to the bone marrow and continue to form antibodies there.
A functioning immune system protects the body from numerous infectious diseases. However, an antibody only recognizes its own antigen. Up to 100 billion different antibodies are therefore required for optimal protection.
The plasma cells are able to produce up to 2,000 antibodies per second. Each B cell has more than 10,000 antibody molecules on the membrane. When a foreign body enters the organism, the appropriate antigens bind to these antibodies. In the further course, there is a multiple cell division, after which the B cells develop into plasma cells. The antibodies mark the pathogen as a foreign body to be eliminated.
A serious note – plasma cells in the blood
Plasma cells in the peripheral blood are a serious indicator of possible liver cirrhosis, viral infection or multiple myeloma. The latter disease has its origin in degenerated plasma cells that multiply uncontrollably. They form 98 percent antibodies.
While multiple myeloma is found at different sites in the skeleton, plasmacytoma is concentrated at a single site. There are six to seven new cases per 100,000 inhabitants in Germany every year. As a rule, multiple myeloma and plasmacytoma appear after the age of 65.
The degenerated plasma cells displace the healthy cells of the bone marrow. This affects the formation of red and white blood cells and platelets. In addition, there is a loss of bone substance, which is associated with bone fractures caused by minor loads or minor injuries.
As the bones break down, larger amounts of calcium enter the circulatory system. In addition to a malfunction of nerves and muscles, damage to the kidneys occurs. Disturbed blood formation leads to anemia and a weakened immune system. The affected person is henceforth more susceptible to infections, especially from bacteria. Reduced platelet formation increases the risk of bleeding.
Doctors often discover multiple myeloma by accident during an examination, since there are no symptoms in the early stages. The protein levels in the blood and urine are usually elevated or the blood sedimentation rate is extremely high. Bone pain usually leads those affected to see a doctor.
For an accurate diagnosis, further examinations such as a puncture of the bone marrow are required. Symptomatic myeloma is present if there are more than 10 percent plasma cells in the bone marrow , abnormal protein in the blood or urine and existing organ damage. On the other hand, doctors speak of an asymptomatic myeloma if no physical symptoms occur despite the 10 percent plasma cells and the diseased protein.
Multiple myeloma is considered incurable. The course can be slowed down significantly with chemotherapy or radiotherapy. In addition, treatments with antibodies or interferon are suitable for positively influencing the course of the disease. If no symptoms occur in the early stages, regular observation takes place instead of treatment. The doctor examines the patient’s blood in order to start treatment as soon as possible. The possible life expectancy from the time of diagnosis is between two and ten years.
Sources
- Rink, Lothar, Kruse Andrea, Haase Hajo.: Immunology for beginners. Spektrum Akademischer Verlag GmbH, Heidelberg, 2012, ISBN 978-3-8274-2439-6 .
- B cell immunology, basics, Rainer H.Staub University of Regensburg https://www.uni-regensburg.de/Fakultaeten/..
