Plasma Cells

Definition

Plasma cells are specialized B cells that produce large quantities of antibodies, playing a crucial role in the immune response. They are formed from activated B cells following exposure to antigens, and their primary function is to secrete antibodies that target specific pathogens, helping to neutralize infections and promote clearance.

5 Must Know Facts For Your Next Test

1. Plasma cells are typically short-lived but can also become long-lived memory plasma cells, contributing to long-term immunity.
2. The antibody production rate in plasma cells can reach up to 2000 antibodies per second.
3. Plasma cells are found primarily in the bone marrow, lymph nodes, and spleen, where they can be closely associated with germinal centers during an immune response.
4. Each plasma cell is specific to one antigen, producing antibodies that recognize and bind to that particular target.
5. The class of antibodies produced by plasma cells can vary (e.g., IgM, IgG) based on signals received during their activation process.

Review Questions

• How do plasma cells contribute to the immune response after B cell activation?
  • Once B cells are activated by encountering specific antigens, they differentiate into plasma cells that produce large quantities of antibodies. These antibodies bind to the corresponding antigens on pathogens, neutralizing them and marking them for destruction by other immune cells. This rapid production of antibodies enhances the body's ability to fight off infections effectively.
• In what ways do plasma cells ensure antibody diversity during the immune response?
  • Plasma cells arise from B cells that undergo somatic hypermutation and class switching during their activation process. This allows for a diverse range of antibodies to be produced, each tailored to target different pathogens. The unique antigen-binding sites formed through these processes enable the immune system to adapt quickly to a variety of infectious agents.
• Evaluate the role of plasma cells in both primary and secondary immune responses.
  • In primary immune responses, plasma cells are generated after the initial exposure to an antigen, leading to the production of antibodies that help eliminate the pathogen. In secondary immune responses, memory B cells can quickly differentiate into plasma cells upon re-exposure to the same antigen, resulting in a faster and more robust antibody response. This illustrates how plasma cells are essential for long-term immunity and rapid responses to previously encountered pathogens.

Related terms

B Cells: A type of white blood cell that plays a key role in the adaptive immune response by producing antibodies and differentiating into plasma cells upon activation.

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

Bone Marrow:

The primary lymphoid organ where B cells mature and differentiate into plasma cells after encountering antigens.