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Introduction to the immune system
MHC class I and MHC class II molecules
B-cell activation and differentiation
Cell-mediated immunity of CD4 cells
Cell-mediated immunity of natural killer and CD8 cells
Somatic hypermutation and affinity maturation
Contracting the immune response and peripheral tolerance
B- and T-cell memory
Anergy, exhaustion, and clonal deletion
B- and T-cell memory
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Key features of the innate immune response are that the cells are non-specific, meaning that they don’t distinguish one invader from another invader, the response is really fast - occurring within minutes to hours, and there’s no memory associated with innate responses.
Once the cell has a unique antigen-specific receptor expressed on its surface it begins traveling through the lymphatic system - passing through lymph nodes in search for the one antigen that fits the receptor perfectly.
If they encounter that antigen, a signal gets delivered to the cell’s nucleus that lead to clonal expansion.
Some of the B and T cells become memory cells, which are basically a pool of lymphocytes that are all set to combat the pathogen, if they encounter it again!
Immunologic memory is sometimes referred to as a secondary or anamnestic response, and it’s different from the primary response.
B and T cells are the two main types of lymphocytes or white blood cells that play a role in the immune response. Both B and T cells can remember previous encounters with foreign antigens, which helps them to quickly and effectively respond to future infections by the same microorganisms.
B cells produce antibodies, which bind to pathogens and mark them for destruction by other immune cells. T cells kill infected host cells or help B cells produce more antibodies. Memory B and T cells persist in the body for many years, providing lifelong protection against reinfection by the same pathogen.
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