Plasma Cells

Definition

Plasma cells are terminally differentiated B-lymphocytes that are responsible for the production and secretion of antibodies, playing a crucial role in the adaptive immune response. They are derived from activated B-cells and serve as the primary effector cells of the humoral immune system.

5 Must Know Facts For Your Next Test

1. Plasma cells are the main producers of antibodies, secreting them at a rate of up to 10,000 per second.
2. Plasma cells are derived from activated B-cells that have undergone clonal expansion and differentiation in response to antigen exposure.
3. Plasma cells lose their ability to express B-cell receptors (BCRs) but gain a high capacity for antibody secretion, becoming the effector cells of the humoral immune response.
4. Plasma cells reside primarily in the bone marrow, mucous membranes, and lymphoid tissues, where they can continuously secrete antibodies for an extended period.
5. The antibodies produced by plasma cells can neutralize pathogens, agglutinate them, or mark them for destruction by other immune cells, such as phagocytes.

Review Questions

• Explain the role of plasma cells in the adaptive immune response.
  • Plasma cells are the key effector cells of the humoral immune response, responsible for the production and secretion of antibodies. They are derived from activated B-lymphocytes that have undergone clonal expansion and differentiation in response to antigen exposure. Plasma cells lose their ability to express B-cell receptors but gain a high capacity for antibody secretion, allowing them to continuously produce and release antibodies that can neutralize pathogens, agglutinate them, or mark them for destruction by other immune cells.
• Describe the relationship between plasma cells and B-lymphocytes in the context of the adaptive immune response.
  • Plasma cells are terminally differentiated B-lymphocytes that play a crucial role in the adaptive immune response. B-cells are responsible for the production of antibodies, a key component of the humoral immune system. When a B-cell encounters an antigen, it becomes activated and undergoes clonal expansion and differentiation, ultimately giving rise to plasma cells. Plasma cells lose the ability to express B-cell receptors but gain a high capacity for antibody secretion, becoming the primary effector cells of the humoral immune response. The antibodies produced by plasma cells can then neutralize pathogens, agglutinate them, or mark them for destruction by other immune cells.
• Analyze the significance of plasma cells in the immune response against pathogens.
  • Plasma cells are essential for the effective elimination of extracellular pathogens and toxins, as they are the primary producers of antibodies, a key component of the humoral immune response. When the body is exposed to an antigen, plasma cells derived from activated B-cells secrete large quantities of specific antibodies that can neutralize the pathogen, agglutinate it, or mark it for destruction by other immune cells, such as phagocytes. The continuous production and secretion of antibodies by plasma cells, particularly those residing in the bone marrow and mucous membranes, provides long-lasting protection against recurrent infections by the same pathogen. This makes plasma cells crucial for the adaptive immune system's ability to mount a robust and sustained response against invading microorganisms, highlighting their significance in the overall immune defense against pathogens.

Related terms

B-Lymphocytes: B-cells are a type of lymphocyte that originates in the bone marrow and is responsible for the production of antibodies, a key component of the humoral immune response.

Antibodies: Antibodies, also known as immunoglobulins, are Y-shaped proteins produced by plasma cells that bind to specific antigens, neutralizing them or marking them for destruction by other immune cells.

Humoral Immune Response: The humoral immune response is the branch of the adaptive immune system that involves the production of antibodies by plasma cells to neutralize and eliminate extracellular pathogens and toxins.