Plasma cells

Definition

Plasma cells are specialized white blood cells that play a crucial role in the immune response by producing and secreting antibodies. They are derived from activated B lymphocytes and are essential for humoral immunity, which involves the production of antibodies that specifically target pathogens and toxins.

5 Must Know Facts For Your Next Test

1. Plasma cells are formed when B lymphocytes encounter their specific antigen and receive help from helper T cells.
2. Once activated, plasma cells can produce thousands of antibodies per second, significantly contributing to the immune response.
3. Plasma cells have a short lifespan, typically living only a few days, but some can become long-lived memory plasma cells that persist in the body.
4. The antibodies secreted by plasma cells can neutralize toxins, opsonize pathogens for phagocytosis, and activate complement proteins for pathogen destruction.
5. In certain diseases, such as multiple myeloma, plasma cells can become malignant, leading to an overproduction of abnormal antibodies.

Review Questions

• How do plasma cells contribute to the adaptive immune response and what is their relationship with B lymphocytes?
  • Plasma cells are crucial for the adaptive immune response as they produce antibodies that specifically target pathogens. They originate from activated B lymphocytes, which undergo clonal selection upon encountering their specific antigen. This activation process, often aided by helper T cells, enables B lymphocytes to differentiate into plasma cells, thereby linking humoral immunity with cellular interactions in the immune system.
• Discuss the role of plasma cells in producing antibodies and how this process impacts humoral immunity.
  • Plasma cells play a vital role in humoral immunity by producing large quantities of antibodies tailored to specific antigens. Once B lymphocytes are activated and differentiate into plasma cells, they begin to secrete antibodies at an astonishing rate. These antibodies circulate in the bloodstream and bind to pathogens or toxins, marking them for destruction or neutralization. This antibody production is key to the effectiveness of the immune response against extracellular threats.
• Evaluate the implications of plasma cell function in health and disease, particularly in conditions like multiple myeloma.
  • The function of plasma cells is critical for maintaining a healthy immune response, as their ability to produce antibodies protects against infections. However, when plasma cells become malignant, as seen in multiple myeloma, they can lead to serious health issues. This condition is characterized by an overproduction of abnormal antibodies that disrupt normal immune function and can cause damage to bones and organs. Understanding plasma cell biology is essential for developing targeted therapies for such diseases and improving patient outcomes.

Related terms

B lymphocytes: A type of white blood cell that plays a key role in the adaptive immune response, responsible for recognizing specific antigens and differentiating into plasma cells upon activation.

Antibodies:

Proteins produced by plasma cells that bind to specific antigens on pathogens, marking them for destruction or neutralization.

Humoral immunity: A branch of the adaptive immune system that involves the production of antibodies by plasma cells, providing protection against extracellular pathogens.