ch.17 Flashcards
How long does adaptive immunity take to build after the first exposure of an invader?
a week or more
what is Adaptive immunity?
defenses that target a specific pathogen after exposure
when is adaptive immunity activated?
when innate defenses fail to stop a microbe
how is adaptive immunity acquired?
through infection or vaccination
T/F Adaptive immunity has memory
T/F Response has molecular specificity
TRUE
TRUE
What two paths is adaptive immunity divided into?
- Humoral immunity
- Cellular immunity
- In adaptive immune response what happens if the same pathogen is encountered again?
- T or F, later interactions (sec. response) with the same foreign substance is slower and less effective due to “memory”
- a stronger secondary response result
- False, faster and more effective due to “memory”
Humoral immunity is mediated by what cell?
What does humoral immunity eliminate?
B-cell mediated
extracellular pathogens and toxins
Cellular immunity is mediated by what cell?
Cellular immunity eliminates what?
T-cell mediated
intracellular pathogens (Intracellular viruses; cancer cells; some intracellular bacteria such as Mycobacterium leprae and Listeria monocytogenes)
- Humoral immunity is mediated by what?
- B cells are created and mature in what?
- B-cells produce antibodies that combat foreign molecules known as ___________?
- B-lymphocytes (B-cells)
- red bone marrow
- antigens
- In response to extracellular antigens, B-cells are triggered to do what?
- Produce _ - _______ _________ called antibodies
- Some B cells form what?
- proliferate and differentiate into plasma cells
- Y-shaped proteins
- long-lived memory B cells
Where do T-cells develop?
Where do they mature?
stems cells in the bone marrow
Thymus
T/F Mature T cells respond to all types of antigens
_____ -____ __________ on the T cell surface recognize __________,
causing the T cells to secrete __________ instead of antibodies
FALSE, they only respond to one type of antigen
T-cell receptors (TCRs)
antigens
cytokines
If B and T cells are adaptive and specific, how do they develop and what do they do?
Early in development of B & T cells, lymphocytes do what?
form and mature to have their specific receptor
What are the 2 subsets of T-cells?
- Cytotoxic T cells
– Helper T cell
Where do T- and B- cells reside once mature?
blood and lymphoid organs
The lymphoid system is designed for what? to bring B- and T-cells in contact with what?
to bring B- and T-cells in contact with what
What percent of B & T cells are deleted?
B cells: 90% clonal
T cells: 98% deletion
What do B cells and T cells have that function to recognize specific antigens?
membrane-bound receptors
- specific antibody the B cell is programmed to make
- does not recognize free antigen; must be presented by body’s own cells
- BCR
- TCR
- Where does an antigen come from?
- what is an immunogen?
- anti-body generator
- Antigen that elicits immune response
good antigens have mostly __________ molecules while weak antigens are ____________?
protein, polysaccharide
Lymph is similar to _________ but contains
__________and lack ________
blood
leukocytes
RBCs
Lymph nodes contain high concentrations of what?
lymphocytes and phagocytes
whole microbial cells and viruses, foreign human or animal cells, plant molecules, and complex molecules with several epitopes are considered good antigens OR bad antigens?
Good antigens
T/F ALL immunogens are antigens, but not all antigens are immunogens
TRUE
T/F Epitopes are the reactive region of an antigen
What do epitopes trigger?
T/F Epitopes are regions of macromolecules
-10 or so amino acids;
shapes; 2D
TRUE
IMMUNE RESPONSE
FALSE, 3D not 2D
small organic molecules that are antigenic but not immunogenic
Haptens
When can haptens function as an immunogen?
when coupled to a larger
carrier protein
What makes something a poor antigen?
small molecules not attached to a carrier
___________: Naive B cell deliver cytokines to T helper cells
___________: plasma cells produce antibodies
___________: antibodies bind to antigen
Activation
Proliferation and differentiation
Effector action and consequence
- T or F, Most are T-dependent antigens requires B cell confirmation from TH cell to be activated?
- T-independent antigens activate B cells (with OR without?) TH cell help; include lipopolysaccharide (LPS) and molecules
with repeating subunits such as some carbohydrates
- True
- WITHOUT TH cell help
- In humoral immunity what are the compact soluble proteins called?
- Ig’s recognize and bind to specific antigens, targeting them for __________
- immunoglobulins (Ig)
- destruction
What do B-cells produce?
What type of proteins do antibodies contain that are soluble?
Antibodies
immunoglobulins
Which antigen-antibody interaction reduces the number of infectious units to be dealt with?
Immobilization/ Agglutination
- An antibody is made up of how many amino acids and what shade do they form?
- How many identical light chains and identical heavy chains joined by disulfide
links?
- Made of four amino acid chains form a Y shape
- Two of each
- When do antigen–antibody complex form?
- Strength of the bond is the
- when antibodies bind to antigens
- affinity
In antigen antibody reaction, all of the following protect the host by what?
▪Agglutination
▪ Opsonization
▪ Neutralization
▪ Activation of the complement system
▪ Antibody-dependent cell-mediated cytotoxicity
tagging foreign molecules or cells for destruction
What is opsonization?
coating the antigen with antibody enhances phagocytosis
what does complement activation cause?
inflammation and cell lysis
What two things does neutralization block?
- adhesion of bacteria &viruses to mucosa
- attachment of toxin
In Antibody- dependent cell mediated immunity, what do antibodies attached to target cells cause?
destruction by macrophages, eosinophils, and NK cells
which cells make 5 different classes of antibodies (IgM, IgG, IgD,
IgA, IgE)
B-cells
Antibodies that came from the same activated B-cell, all have the same what?
antigen binding site
name the antibody class that is:
▪Major Ig in secretions (breast milk, saliva, tears, mucus)
-60-70% of total antibody production
IgA
- Where is IgA found and how much percent?
- IgA antibody class is:
- monomer in __________
- __________ in secretions
- ▪Found in secretions
▪10 - 13 % of serum Ab - monomer in serums
dimer in secretions
Which antibody class is the most abundant in the serum ?
T/F The structure of this antibody is polymer
IgG is the only antibody that can cross what?
IgG
FALSE, its structure = MONOMER
the placenta
DAILY PRODUCTION of which antibody class is greater than any other Ig class?
IgA
activation of B-cells
clonal deletion eliminates harmful B cells in which cell and where?
Memory cells, bone marrow
B cells once activated, differentiates into what 2 things?
- Memory cells
- Antibody-producing plasma cells
- Memory cells
IgE is responsible for what?
T/F IgE is barely detectable in circulation
Mediate hypersensitivity reactions
(hay fever, asthma, hives,
anaphylactic shock)
TRUE
Which antibody class is <1% of total antibody circulation?
T/F this antibody class is maturation of antibody response
IgD
TRUE
Where do B cells reside and interact with antigens?
T/F Every B cell has the same BCR (B cell Receptor)
in lymphoid
organs (spleen and lymph nodes)
FALSE, every b cell has a UNIQUE receptor
In Clonal SELECTION when is the B cell activated?
when its B-cell
receptor (BCR) binds to its antigen
- Dendritic cells, macrophages, and B cells are considered which kind
of cell (APC)? - what activates macrophages?
- Antigen presenting cell
- cytokines
In Clonal EXPANSION what two things do the activated B cells proliferate and differentiate into?
-Plasmocytes/plasma cells
-memory B cells
In cellular immunity
Major Histocompatibility complex (MHC I and II) is used for what?
list the 3 below
display processed antigens
1. dendritic cells
2. macrophages
3. B cells
Name the two types of MHC
- Class I MHC
- Class II MHC
MHC class I binds what? MHC class II?
MHC I: endogenous antigen (T-cytotoxic cells)
MHC II: exogenous antigen
(T-Helper cells)
- where is Class I MHC present?
- In Class I MHC, antigen-presentation happens to which cells?
- on the membrane of ALL nucleated cells
- T cytotoxic cells
TC cells recognize antigen presented on MHC
class ____ molecules
TH cells recognize antigen presented on MHC
class _____ molecules
TC cells respond to _____________antigens
TH cells respond to _______
antigens
CLUSTER DIFFERENTIATION (CD)
TC cells usually have _____
* TH cells usually have ______
MHC Class I
MHC Class II
endogenous
exogenous
CD8
CD4
- Which Class of MHC is on the surface of antigen-presenting cells (APCs) including B cells, macrophages, dendritic cells?
- Antigen-presentation to which cells in this class of MHC?
- Class II MHC
- T helper cell
T or F The role of T cells is different from
B cells?
True
What two things do T-cells combat?
- intracellular pathogens
- abnormal host cells such as cancer cells
- T cells never produce ____________
- does T cell receptor bind with free antigen?
antigens
no, Antigen must be present by APC
- which 2 cells help innate and adaptive immune cells?
- which 2 cells help us fight viral infections and cancers?
- CD4+ or TH cells
- CD8+ or TC cells
What eliminates immature and self-reactive T-cells?
Thymic selection
What is known as programmed cell death?
What does it prevent?
Apoptosis
- spread of infectious viruses into other cells
*T cell receptors (TCRs) recognize antigens
presented where and by what?
on MHC II by Antigen presenting cells
(APC)
TH cells produce cytokines and activates what 3 things?
B-cells, macrophages and CTLs (cytotoxic T-lymphocytes)
_______ ________: immune response on first exposure to an
antigen
* ________ _______: occurs after the second exposure to an
antigen
Primary response
Secondary response
- T cytotoxic cells are activated into what?
- CTLs recognize intracellular antigens presented by?
- CTLs Induce __________ in target cell
- CTL releases what 2 things?
- cytotoxic T lymphocytes (CTLs)
- MHC I
- apoptosis
- perforin and granzymes
what do Granular leukocytes destroy?
-use perforin and granzymes
- T or F Not stimulated by antigen, Hence considered as a part of innate immune response?
cells that don’t express MHC I
true
- what is Naturally acquired immunity?
- Immunization mimics these
events by inducing what?
- acquisition of adaptive immunity through natural events
- artificially acquired immunity
Define class switching
T/F Class switching is short and does not last many days
Initial IgM response shifts to IgG,
IgE, or IgA, occurs
FALSE, it lasts many days
What is known as the relative amount of antibody in the serum?
Antibody titer
Active immunity results from what?
T/F Active immunity can develop
naturally (following illness)
When can active immunity develop artificially?
immune response
upon exposure to an antigen
TRUE
after immunization
- which type of adaptive immunity:
- Occurs naturally during pregnancy
* IgG from mother crosses placenta (Infers protection to the baby)
passive immunity
- How does passive immunity occur?
- Artificial passive immunity involves
transfer of what?
- occurs naturally as result of breast feeding
- antibodies produced by another person or animal
What are the four types of immunity?
- Naturally acquired active
immunity (infection) - Naturally acquired passive
immunity (transplacental) - Artificially acquired active
immunity (immunization) - Artificially acquired passive
immunity (antibodies)
