Plasma cells

Definition

Plasma cells are specialized white blood cells that originate from B lymphocytes and are responsible for producing antibodies. These cells play a crucial role in the humoral immune response by recognizing and binding to specific antigens, thereby neutralizing pathogens and marking them for destruction by other immune cells.

5 Must Know Facts For Your Next Test

1. Plasma cells are derived from activated B lymphocytes after they encounter their specific antigen and undergo clonal expansion.
2. These cells can produce thousands of antibody molecules per second, which allows for a rapid response to infections.
3. Plasma cells have a short lifespan, usually lasting for a few days to weeks, but some can differentiate into long-lived memory plasma cells that provide lasting immunity.
4. The antibodies produced by plasma cells can neutralize toxins, block viral entry into cells, and opsonize pathogens for enhanced phagocytosis by immune cells.
5. Disorders involving plasma cells can lead to conditions like multiple myeloma, where abnormal plasma cell proliferation occurs.

Review Questions

• How do plasma cells contribute to the adaptive immune response and what is their relationship with B lymphocytes?
  • Plasma cells play a vital role in the adaptive immune response by producing antibodies that target specific antigens. They arise from activated B lymphocytes after these cells encounter their corresponding antigen, leading to their proliferation and differentiation. This process enhances the body's ability to effectively respond to pathogens through the production of large amounts of antibodies, which directly neutralize or mark invaders for destruction.
• Discuss the lifecycle of a plasma cell and its significance in maintaining immunity.
  • The lifecycle of a plasma cell begins when a B lymphocyte is activated by an antigen. Upon activation, it undergoes clonal expansion and differentiation into plasma cells, which produce large quantities of antibodies. Although plasma cells have a relatively short lifespan, some can become memory plasma cells, which persist long-term in the body. This persistence is crucial as it allows for a quicker and more effective antibody response upon re-exposure to the same pathogen, thus maintaining long-term immunity.
• Evaluate the impact of plasma cell dysfunction on health, particularly in relation to diseases like multiple myeloma.
  • Dysfunction of plasma cells can significantly impact health, particularly evident in diseases such as multiple myeloma. In this condition, abnormal proliferation of plasma cells leads to an overproduction of non-functional antibodies, disrupting normal immune function and causing damage to bones and organs. Additionally, this unchecked growth compromises the body's ability to fight infections, resulting in increased susceptibility to diseases. The study of plasma cell behavior and regulation is vital for understanding such pathologies and developing targeted therapies.

Related terms

B lymphocytes: A type of white blood cell that matures in the bone marrow and is essential for the adaptive immune response, particularly in the production of antibodies.

Antibodies: Proteins produced by plasma cells that specifically bind to antigens, neutralizing pathogens or marking them for destruction by other immune components.

Humoral immunity: A component of the adaptive immune response that involves the production of antibodies by plasma cells, providing defense against extracellular pathogens.