Adaptive Immunity Flashcards
What are some key differences between active and passive immunity? Please give examples.
Self created vs non self created
strength of immunity
Define an antigen.
Usually a foriegn substance that activates immune response. Usually made of proteins, and are parts of a virus, bacteria, or helminth.
Describe the process by which B-lymphocytes are activated if the antigen is T-independent.
B cell binds to t-independent at multiple spots and is activated directly and proliferates into mem B and plasma.
Define epitope and hapten.
hapten: a small antigen that must bind to a carrier molecule to bind to an antibody. Allergens.
epitope- antigenic determinant, portion of antigen that is binding to the antibody.
Which type of cytokine is a key co-stimulator of T cell activation?
interleukins
Describe the process that results in an antigen-presenting cell. Which cells can act as APC’s?
Cells are dendritic, macrophages, and activated B cells.
antibody titer
measurement of the amount of antibodies present after exposure to an antigen
Describe the 5 classes of antibodies (MADGE). For each describe its structure, function and relative percentage in the blood (most to least).
Most to least
IgG- crosses placenta, immune response
IgA- in secretions
IgM- first to be secreted by plasma cells
IgE- allergic response and attached to basophils
IgD- unknow use, possibly receptor
What does it mean for a B or T cell to immunocompetent? What do they acquire?
They have their unique receptors.
Distinguish between exogenous and endogenous antigen as well as autoantigens.
Exogenous-outside of host cell
Endogenous- inside host cell (virus)
autoantigen- not foreign normal self tags on cells.
How do activated cytotoxic T cells kill their targets?
perforin-granzyme cytotoxic pathway- perforins poke holes in cells and granzymes destroy them with enzymes
CD95 cytotoxic pathway- CD95 glycoprotein present on most cells and binds to CD95L receptor on Tc cells. Activates enzymes that cause cell death
helper T cells
Director of the immune response and stimulate cytotoxic t cells and b cells.
opsonization
coating a microbe with antibodies to enhance phagocytosis
neutralization
cages off antigen and prevents from damaging cells
memory T cells
clones of the original Th cell that remember an antigen and create a stronger and longer immune response the second time
How does the production of antibody in response to a secondary exposure to an antigen compare to the primary response?
Secondary response happens faster, with more antibodies, and lasts a longer time.
Describe how T cells achieve self-tolerance and where
Happens in thymus
Positive selection: cells that recognize MHC are kept
Negative selection: cells that do not recognize autoantigens are kept
How are T-dependent and T-independent antigens different? Which cells can be activated by T-independent antigens?
T-dependent antigens require a Th cell response to activate Tc and B cells.
T-independent antigens can activate B cells independently.
Which cells play a role in adaptive immunity?
B+T lymphocytes
Briefly describe the structures of the lymphatic system. Which structures are primary structures and which are secondary structures.
Primary: Red bone marrow and thymus
Secondary: lymph nodes, MALT, spleen
How is it that we develop a memory for an antigen? What cells and cell products provide this memory?
Memory T and B cells
Describe some characteristics of adaptive immunity.
specificity, clonality, self-tolerance, and memory
Distinguish between MHC-I and MHC-II.
MHC 1- on all nucleated cells
MHC 2- only on antigen-presenting cells
List and describe the four ways in which immunity is acquired.
artificially acquired active immunity- vaccine
artificially acquired passive immunity- immunotherapy
naturally acquired active immunity- got sick
naturally acquired passive immunity- mother-child
