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Describe that memory cells are not produced in passive immunity
Describe that memory cells are not produced in passive immunity
Answer
Memory cells are not produced in passive immunity, which is a key distinction between passive and active immunity. Here’s an explanation of this concept:
Understanding Passive Immunity
- Definition: Passive immunity occurs when antibodies are transferred from one individual to another, providing immediate protection without the recipient’s immune system actively producing those antibodies. This transfer can occur naturally, such as from mother to infant during pregnancy and breastfeeding, or artificially through antibody-containing treatments.
- Source of Antibodies: In the case of maternal passive immunity, antibodies (primarily immunoglobulin G, or IgG) are passed from the mother to the fetus through the placenta during pregnancy and through breast milk after birth. These antibodies help protect the infant against infections during the early months of life.
Lack of Memory Cell Production
- No Immune Response Activation: Since passive immunity involves the direct transfer of antibodies rather than the immune system’s response to a pathogen, there is no activation of B cells or T cells. As a result, memory cells—specialized immune cells that remember specific pathogens—are not formed.
- Short-Term Protection: The antibodies provided through passive immunity offer temporary protection, typically lasting only a few weeks to a few months, as they do not stimulate the recipient’s immune system to generate its own long-lasting memory cells.
- Contrast with Active Immunity: In contrast, active immunity results from exposure to a pathogen (either through infection or vaccination), which activates the immune system. This activation leads to the proliferation of B and T lymphocytes and the formation of memory cells that provide long-term immunity against future infections by that pathogen.
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