Clonal selection Flashcards
the process that highly specific
lymphocyte receptors recognize specific antigen
Clonal selection:
clonal expansion is when?
Activated lymphocytes
undergo cell proliferation and differentiation to
form clones of antigen-specific effector cells that mediate adaptive immunity.
What is tolerance and what does it do?
tolerance ensures that the immune system avoids destroying host tissue
* Many of the random rearrangements used to create B and T cell receptors
could be anti-self
Tolerance:
Lymphocytes with self-reactive receptors are normally eliminated during development or are functionally inactivated →
This leads to…
- Lymphocytes with self-reactive receptors are normally eliminated during development or are functionally inactivated → immune system combats
foreign antigens, not self-antigens (autoantigens, components of normal
tissue)
Why is tolerance so important?
Tolerance helps to keep these anti-self recognition molecules/cells from
circulating in the bloodstream
Immunological memory is hallmark of which type of immunity?
adaptive immunity
Explain the steps in immunological memory starting from primary response to second exposure
- Primary response is initiated upon first exposure to an antigen (~14
days)
Memory lymphocytes are left behind after antigen is cleared - A second exposure to the same antigen re-stimulates
memory lymphocytes reactivated faster (2~3 days), more
significant, better response (allow vaccines to work) - Memory is NOT present in innate immunity
Is memory present in innate immunity?
NO!!!!!