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How do memory B cells and memory T cells improve later immune responses?
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immune system
Stimulation of immune response by activated helper T cells. Activated by complex interaction with molecules on the surface of a macrophage or some other antigen-presenting cell, a helper T cell proliferates into two general subtypes, TH1 and TH2. These in turn stimulate the complex pathways of the cell-mediated immune response and the humoral immune response, respectively.
Memory B cells and memory T cells are essential components of immunological memory, which allows the body to mount a faster and more effective defense upon re-exposure to a previously encountered antigen.1
During a primary immune response, clonal selection produces both short-lived effector cells and long-lasting memory cells. While effector cellsâsuch as plasma cells that secrete antibodiesâactively fight the initial infection, memory cells remain in the tissues and circulation for months or even years.12
When the body is re-exposed to the same pathogen, these memory cells recognize the antigen and trigger a secondary immune response. Specifically:21
- Rapid Response: Memory B cells quickly divide to form a new population of antibody-secreting plasma cells, leading to a swift rise in protective antibody levels that can prevent disease from taking hold.2
- Self-Renewal: Memory cells also produce additional memory cells, ensuring the immune system maintains its ability to respond to future encounters with the same pathogen.21
This mechanism provides the basis for long-term immunity to various infections.1