Chapter 17: Adaptive Flashcards
Who proposed the theory of immunity?
Ehrlich
What year did Ehrlich propose the theory of immunity?
1890
______ are agents that are targeted by the adaptive immune system
Antigens
Antigens are composed of many small regions. Each is called an _____
epitope
What is the other name for epitopes?
Antigenic determinants
The best antigens are made of what?
Glyco proteins
an ______ is approximately 7 amino acids in size.
epitope
What is something specific about B and T cell recognizing epitopes?
Each individual B or T cell will only recognize one epitope ever
The epitope that activates the lymphocyte is what sets its ______
specificity
Antigen recognition is set _____ and forever during lymphocyte development
randomly
Are multiple epitopes recognized from a single large antigen?
Yes
Because multiple epitopes are recognized from a single large antigen, many different……
many different B and T cells are activated by that antigen
Epitopes first match to _____ cells, which is a fully functional lymphocyte that has not been activated
naive cells
How many different T cell specificity’s are there?
10^18
How many different B cell specificity’s are there?
10^15
How long does it take for an epitope to match to a naive cell?
18-36 hours
Is an epitope matching to a naive cell a rare or common event?
Rare
The specific ______ on a lymphocyte must bind to the correct epitope
receptor
Will most lymphocytes die as naive or activated?
Naive
____ ____ is where each newly activated lymphocyte will rapidly reproduce daughter cells
clonal expansion
Are there more T cell or B cell different cell specificity’s?
More T cell (10^18)
How many copies will a newly activated lymphocyte make of itself?
about 1,000
Does clonal expansion take more or less time than epitope match?
Same time…18-36 hours
The receptor that binds to the epitope is called….
Surface bound antibody (slg)
What is the short name for a surface bound antibody?
slg
What can bind to a naked, free floating antigen?
the slg (surface bound antibody)
Is antigen recognition set randomly or specifically?
randomly
What does a naive b cell need to become fully activated?
hormonal help
A naive B cell needs hormonal help to become fully activated. What help is that?
TH2–CD4+ (Th2 is the 2nd of 3 helper t cells)
_____ cells have a very large cytoplasm with a high amount of rough ER
plasma cells
Why do plasma cells have a large cytoplasm with a high amount of rough ER?
To be able to secrete 10,000 antibodies per second.
Plasma cells die after a few ____
weeks
CD5+ are:
T-independent B cells. Also called intraperitoneal B cells
CD5+ are activated by…..
large, repeating polysaccharide antigens
CD5+ intraperitoneal B cells do not need stimulation from….
CD4+ T cell hormones
T-independent B cells generally induce….
fairly weak immune responses.
Which cells are not active in children until about 2 years of age?
CD5+ intraperitoneal cells
Do T cells respond to free floating antigens?
No
What do plasma cells have a high amount of? along with what?
rough ER along with a large cytoplasm
T cells can only be activated by…..
an antigen that has been processed by other cells
Other cells chop up ____ and display them inside of a protein called ______
chop up antigens, display them on the inside of a protein called a MHC.
MHC stands for
Major histocompatibility
____ can only recognize the proper epitope if the fragment of an antigen is held in a molecule of MHC
T cells
CD8+ cells recognize MHC __ and CD4+ cells recognize MHC __
CD8+ cells recognize MHC I and CD4 recognize MHC II
CD8+ recognizes antigen held in which MHC?
Type I
MHC I is expressed by which cell types?
Almost all
MHC I displays fragments of ______ _____
cytoplasmic proteins
A correct epitope match with CD8+ causes Tc to…..
kill the cell displaying the proper epitope.
CD4+ T cells recognize epitope held in…
MHC II
MHC II is expressed only in…
APC’s
APCS are…
Antigen presenting cells
List the APC’s
Dendritic cells, B cells ,and macrophages
What do APC’s do?
Internalize the antigen and chop it into pieces and puts it on the outside of the cell
Why is the antigen fragment displayed on the surface of the APC?
To recruit T cell help
A correct epitope match with CD4 causes….
TH to dump stimulatory hormones on the cell that is displaying the proper epitope.
What results in a more effective immune response?
A second exposure to the same antigen
What is the exact mechanism of immune memory?
Still unknown.
Formed memory cells can survive for _____
years
Antibodies are secreted from ___ ___
plasma cells
What shape are antibodies
Y-shaped
____ are composed of 4 polypeptide chains
antibodies
How much do antibodies weigh?
150kDa)
What are antibodies called in blood plasma?
Gamma globulin
The ___ of the antibody contains two variable regions
Top
The ___ of the antibody, the stem, is called the constant region
bottom
How many constant regions are there?
5
What are the five different antibody constant regions?
IgA, IgD, IgE, IgG, and IgM
This antibody constant region is found in body secretions as dimers
IgA
This antibody constant region is found on the surface of maturing and naive B cells
IgD
What is the rarest antibody class?
IgE
What is the most common class of antibody in blood plasma?
IgG
What is the common antibody class for slg?
IgM (slg is surface bound antibody)
Which antibody class is released as a pentamer? (J chain)
IgM
Which antibody class is associated with allergies?
IgE
This antibody constant region is sometimes found in blood plasma as monomer
IgA
Which antibody class easily stimulates mast cells?
IgE
Which antibody class has poor quality antibodies? what makes them poor quality?
IgM…Weak binding ability
_____ can class switch to IgA, IgE or IgG later
IgM
Which antibody class moves well out of the blood vessel and into tissue beds? (plasma to interstitial fluid)
IgG
Which antibody class is the only one able to cross the placenta?
IgG
Can antibodies by themselves kill or destroy?
No
What do antibody’s do?
Recruit immune cells and use immune proteins to attack antigen
What are the five ways antibodies recruit/use?
- Opsonization
- Agglutination
- Neutralization
- Complement activation
- Antibody-dependent cellular cytotoxicity (ADCC)
______ is when the antibody is attached to the foreign object, making it easier to phagocytize
Opsonization
Which antibody recruitment/usage is being described?
“Antibodies use their two identical binding sites to bind multiple antigens”
Agglutination/Precipitation
Which antibody recruitment/usage is being described?
“Antibody physically blocks toxin or pathogen from attaching to human cell”
Neutralization
Which antibody protection/recruitment is difficult to accomplish in real life?
Neutralization
Which antibody protection is the classical activation pathway for the complement cascade?
Complement activation
The complement activation works using ___ and ____ ONLY.
IgM and IgG
What does ADCC do?
Utilizes immune cells to attack labeled targets without using phagocytosis
_____ is effective against very small antigens of bacterial toxins and virions
Neutralization
The immune complexes associated with agglutination/precipitation enhance phagocytosis because….
Large masses are easier to find and grab. They contain multiple antigens that are then destroyed by a single event
Which antibody class is most effective with agglutination/precipitation because of its multiple binding sites?
IgM
Which antibody recruitment/usage is being described?
“A large mass of antigens and antibodies become heavy and sink”
Agglut/Precip
The immune complex is associated with which antibody protection?
Agglut/precip
