test 1: questions Flashcards
1
Q
Pattern recognition receptors recognize:
a. evolutionarily conserved microbial structural components absent from eukaryotic cells
b. peptide-MHc comPlexes
c. viral reverse transcriPtase
d. of the above
A
a. evolutionarily conserved microbial structural components absent from eukaryotic cells
2
Q
Proper development of mucosal immune tissues requires:
a. eating a nutrient rich diet
b. exercise
c. microbial colonization
d. inflammation
A
c. microbial colonization
3
Q
The evolutionary relationship between Drosophila Toll and the mammalian Toll-like receptors (TLRs) and interleukin-1 receptors (IL-IR) is apparent from the similarity between:
a. Toll, TLRs and lL-1R all respond to the cytokine TNF
b. intracellular TlR domain is the same in Toil, TLRs, and lL-1R
c. Toll, TLRs and lL-1R have the same extracellular domain
d. is no evolutionary relationship between Drosophila Toll and the mammalian TLRs
A
b. intracellular TlR domain is the same in Toil, TLRs, and lL-1R
4
Q
Toll-like receptor signaling is important for adaptive immune responses to infection because:
a. it upregulates expression of co-stimulatory molecules and cytokines by antigen presenting cells
b. it induces T cell receptor rearrangement to allow detection of specific antigens
c. it induces B cell receptor rearrangement to allow production of antigen-specific antibodies
d. it inhibtis microbial colonization
A
a. it upregulates expression of co-stimulatory molecules and cytokines by antigen presenting cells
5
Q
what does ELISA stand for
A
Enzyme-linked immunosorbent assay
6
Q
What is the difference between affinity and avidity when considering antibody-antigen interactions?
A
affinity = 1 fab region-> intrinsic affinity
avidity = more then one Fab region -> functional affinity
7
Q
What is FACS
A
fluorescence activated cell sorter
sort based on granularity of cell
size of cell
flourescence
add antibodies with added stain to determine if a specific cell type is in a sample
8
Q
how does complement know self
A
DAF
MCP
H and I
9
Q
what are the three effector functions of complement
A
recruitment of inflammatory cells by anaphylatoxins
opsonization of pathogen to increase killing- phagocytosis
perforation of pathogen by MAC
10
Q
producer cell and effect for
IL-12
IL-5
IL21
IL10
IL17
A
12→ T cells → T cell growth factor
5 → TH2 cells → epsonophil growth factor
21 → T cell → important for TFH help for B cells
10 → T cells and macrophages → inhibit T cells and macrophages
17 → T cells → proinflammatory, increases neutrophil recruitment
11
Q
producer cell and effect for
IL-1
IL-2
IL-4
IL-5
A
12
Q
producer cell and effect for
IL-6, 7, 10, 12, 13
A
13
Q
producer cell and effect for
IL-15, 17, IFN gamma, TNF
A
14
Q
producer cell and effect for
TGF beta, IL-21
A
15
Q
Cross presenting
A
can take an outside antigen and present it on a MHC class 1 instead of an MHC class II
CTL response on hematopoetic APCs
16
Q
how can MHC see so many antigens
A
anchor residues see certain motifs everything else can be different
MHC class I → only 9 amino acids
MHC class 2 → not limited by length of amino acids
17
Q
steps of leukocyte extravastation
A
capture and rolling → selectins → sialyl lewis X
arrest and crawling CAM → integrins and chemokines to chemokine receptors
diapedesis- PECAM - PEcAM1 and CD99 and CD99 (paracellular or transcellular
migration → chemotaxis through perivascular space
18
Q
which selectin are expressed by endothelial cells and what do they do?
A
E-selectin
bind to sialyl lewis X on leukocyte (capture leukocyte)
19
Q
what does RAG gene do?
A
enzyme that causes somatic recombination of VDJ part of the light chain of antibodies
20
Q
4 components of the innate immune system
A
physical barriers
enzymes (chemical barriers)
phag cells
complement system
21
Q
Which antibody isotype is the most prevalent in serum and exhibits the widest diversity of functions?
A
IgG
22
Q
The major immunoglobulin class produced after primary exposure to antigen is
A
IgM
23
Q
2 antibody effector mechanisms
A
neutralization → make toxin not toxic to body by binding
opsonization → tag antigen to be eaten
24
Q
which antibody is most likely in the gut
A
IgA
25
which antibody plays a direct role in actue hypersensitivity reaction
IgE
26
The innate immune response:
Select one:
a. Has immediate and induced components
b. Can distinguish between “self” and “non-self” through pattern recognition receptors
c. Directs and shapes the quality of the adaptive response
d. Is the most ancestral type of immune response
e. All of the above
e. All of the above
27
What is INCORRECT regarding cytokines:
Select one:
a. They alert the body of an infection, in part by causing fever
b. They instruct and activate the adaptive immune response
c. They communicate information among cells of the immune system to shape the immune response
d. They neutralize pathogens upon infection
e. They act both at the local and systemic levels
d. They neutralize pathogens upon infection
28
Examples of essential components of the innate immune system are:
Select one:
a. Defensins, chemokines, T cells, complement
b. Complement, cytokines, phagocytes, T cell receptor
c. Complement, pattern recognition receptors, cytokines, phagocytes
d. Defensins, complement, co-stimulatory molecules, antibodies
e. B cells, cytokines, chemokines, T cells, pathogen recognition receptors
c. Complement, pattern recognition receptors, cytokines, phagocytes
29
The thymus:
Select one:
a. Grows as we age and is where B cells mature
b. It doesn’t change in size as we age and is where both B and T cells mature
c. Is a secondary lymphoid tissue that involutes as we age
d. Involutes with age and is where B cells mature
e. Is the primary lymphoid tissue where T cells mature
e. Is the primary lymphoid tissue where T cells mature
30
Animals lacking innate immunity:
Select one:
a. Have delayed but efficient adaptive immunity
b. Can’t control pathogens and pathogens grow to high numbers in the infected organism
c. Nothing happens as adaptive immunity kicks in instead
d. Control pathogen growth early on, but do not clear the pathogens from the organism
e. None of the above
b. Can’t control pathogens and pathogens grow to high numbers in the infected organism
31
Adaptive immunity:
Select one:
a. Is non-clonal and contains identical receptors on all cells of the same lineage
b. Generates memory responses that protect against re-infection with the same pathogen
c. Is the first line of defense against infection
d. Is immediate and there is no lag time after antigen exposure
e. All of the above
b. Generates memory responses that protect against re-infection with the same pathogen
32
Which of these statements is true regarding lymph nodes? They...
Select one:
A. Are encapsulated secondary lymphoid tissues connected to both the circulatory and
lymphatic systems
B. Are present in all animals from reptiles to mammals
C. Have an inverted organization in pigs compared to other mammals
D. a and c
E. b and c
D. a and c
33
Toll Like Receptors (TLRs) are present in a number of different cellular compartments and activate innate immune defense in response to recognizing their ligands. Choose the correct statement that describes the logic of TLR localization
Select one:
a. plasma membrane TLRs recognize nucleic acids while endosomal TLRs recognize microbial surface structures
b. plasma membrane TLRs recognize the T cell receptor while endosomal TLRs recognize the B cell receptor
c. plasma membrane TLRs recognize microbial surface structures while endosomal TLRs recognize the B cell receptor
d. plasma membrane TLRs recognize microbial surface structures while endosomal TLRs recognize nucleic acids
none of the above
d. plasma membrane TLRs recognize microbial surface structures while endosomal TLRs recognize nucleic acids
34
Pathogen Associated Molecular Patterns (PAMPs) are recognized by:
Select one:
The T cell Receptor
Cytokine Receptors
The B cell Receptor
Pattern Recognition Receptors
NK cells
Pattern Recognition Receptors
35
Phagocytes are crucial components of innate immunity. Which of these is not a mechanism used by
phagocytes to mediate host defense?
Select one:
providing a physical barrier
production of antimicrobial peptides
engulfment of foreign particles
production of reactive oxygen and nitrogen species
providing a physical barrier
36
Systemic bacterial infection can cause a lethal pathology known as sepsis. This is due to:
Select one:
overexuberant production of innate inflammatory mediators leading to systemic edema, loss of blood volume, and organ failure
direct effects of bacterial toxins causing organ damage
excessive bacterial burdens in tissues leading to organ failure
overexuberant production of innate inflammatory mediators leading to systemic edema, loss of blood volume, and organ failure
37
Which of these statements correctly describes the relationship between the innate and adaptive
immune systems?
Select one:
A. The innate immune system is the first line of defense and the adaptive immune system is only activated if the innate immune system cannot contain the pathogen
B. The innate immune system is the first line of defense and also provides instructive signals to the adaptive immune system that appropriately tailor the adaptive response to the nature of the pathogen threat
C. The innate and adaptive immune systems function separately to provide optimal immune defense
D. The adaptive immune system is the first line of defense and the innate immune system is only activated if the adaptive immune system fails to contain the pathogen
E. (A) and (B) are correct
E. (A) and (B) are correct
38
Macrophages produce critical inflammatory mediators to promote clearance of infection. These
inflammatory mediators act by (chose the best answer):
Select one:
increasing vascular permeability
activating the vascular endothelium
producing chemokines that recruit other cells
activating lymphocytes
all of the above
all of the above
39
Which molecule is not involved in activation step of the classical complement pathway?
Select one:
IgG
CRP
IgM
MBL
C1
MBL
40
Which is not an effector functions of the complement pathway?
Select one:
Blood coagulation
Phagocytosis
Formation of MAC
Removal of soluble immune complexes
Recruitment of inflammatory cells
Blood coagulation
41
Regulation of complement is essential to ensure host tissue is not damaged during pathogen attack. From the list below, which protein is a soluble complement regulator that is recruited to the host cell plasma membrane to inactivate C3b?
Select one:
MCP
CR1
Factor D
Factor H
C8
Factor H
42
Which protease of the alternative pathway is structurally similar to C2?
Select one:
C1r
MASP-2
Factor D
Factor I
Factor B
Factor B
43
The term zymogen refers to a:
Select one:
Carbohydrate recognition domain
Pathogen associated molecular pattern
Inactive enzyme
Complement control domain
Immunoglobulin subclass
Inactive enzyme
44
Which molecule binds covalently to pathogen associated carbohydrates and proteins via a thioester
motif?
Select one:
C1
MBL
DAF
C3
C5
C3
45
Which of these is a C3 convertase?
Select one:
C2a-C3b
C3b -Bb
C1q-C1r
C3b-Bb
CR1-iC3b
C3b-Bb
46
If I want to differentially detect by ELISA two viral antigens that are 99% identical at the amino acid
level, I should use:
Select one:
Polyclonal antibodies that have been produced by injecting each separate viral antigen to a different rabbit
Monoclonal antibodies that recognize common epitopes on both viral antigens
Polyclonal antibodies that have been produced by injecting the two viral antigen into the same rabbit
Monoclonal antibodies that recognize the epitope responsible for the 1% difference between the two antigens
All of the above
Monoclonal antibodies that recognize the epitope responsible for the 1% difference between the two antigens
47
When isotype switching occurs, the following region in the immunoglobulin molecule changes:
Select one:
A. The variable region of the heavy chain
B. The constant region of the heavy chain
C. The variable region of the light chain
D. Both the variable and constant region of the heavy chain
E. A and C are correct
B. The constant region of the heavy chain
48
Where does antigen-dependent B cell clonal expansion occur?
Select one:
A. In the bone marrow
B. In lymph nodes
C. Underneath your nails
D. In the spleen
E. B and D are correct
E. B and D are correct
49
Do B cells play other roles in addition to secreting immunoglobulins?
Select one:
Yes, certain B cell types can phagocytose large particles
Yes, they can produce several important pro-inflammatory cytokines
Yes, they can produce several important anti-inflammatory cytokines
Yes, the can present antigen to T cells
All of the above are correct
All of the above are correct
50
IgA is an immunoglobulin:
Select one:
A. That strongly activates the complement system
B. That has a key role in fighting helminths infections
C. That is specialized in mucosal immunity
D. That is critical in triggering of allergic reactions
E. B and D are correct
C. That is specialized in mucosal immunity
51
Why is IgE important:
Select one:
Because it plays a key role against helminth infections
Because is a really cool immunoglobulin with three different antigen binding sites
Because it is the only immunoglobulin that can activate complement
Because it is an immunoglobulin specialized in mucosal immunity
None of the above are correct
Because it plays a key role against helminth infections (parasitite)
52
Why is negative selection of B cells an important mechanism for organismal survival?
Select one:
A. Because it gets rid of B cells that react with viruses
B. Because it selects B cell clones that recognize HIV infected cells
C. Because it allows for autoimmunity
D. Because it eliminates B cells that recognize healthy host tissue/cells
E. C and D are correct
D. Because it eliminates B cells that recognize healthy host tissue/cells
53
Dendritic cells use germline-encoded receptors that sense pathogen or DAMPs. Pick the correct combination of receptor for each.
Select one:
TLR and MHC II
RIG-1 and FcR gamma
Lysosomal hydrolases and complement receptor 3
TLR and DEC-205
TLR and P2XR
TLR and DEC-205
54
Important differences between immature and mature dendritic cells include: (choose the correct
combination)
Select one:
Immature DC are highly phagocytic and express low levels of TCR
Mature DC are cytotoxic and migrate to the draining LN to prime naïve T cells
Immature DC are motile cells that express lower levels of MHC II than mature DC
Mature DC are a major source of cytokines for T cell priming but immature DC are immobile
A and C
Immature DC are motile cells that express lower levels of MHC II than mature DC
55
Dendritic cells serve as an important source of cytokines for naïve T cell polarization into mature
CD4 T helper cell subsets. The cytokines produced by DC for TH17 polarization are:
Select one:
IL-4 and IL-10
GMCSF and IL-2
IL-6 and TGF-beta
IL-12p70 and IFN-gamma
IL-1 alpha and IL-1 beta
IL-6 and TGF-beta
56
Dendritic cells are located primarily at mucosal barrier tissue sites. Select the correct tissue site and DC population. DCs located in the ______ are called _____ and are important for sensing pathogens or antigens that affect this tissue.
Select one:
Liver, kuppfer dendritic cells
Lamina propria, intestinal dendritic cells
Epidermis, langerhans cells
Trachea, aerophilic dendritic cells
Lung, alveolar dendritic
Epidermis, langerhans cells
57
Antigen presenting cells that express Class II take up antigen into endosomes, where the proteins are broken down into peptides. Class II gets from the ER to an endosome, which is facilitated by:
Select one:
proteins encoded within the cytoplasmic proteasome
the invariant chain
several different lysosomal proteins contained with the endosome
the transporter associated with antigen processing (TAP)
Clip, which inhibits peptides from binding to Class II in the ER
the invariant chain
58
In order for T cells to function as effector T cells, they require exposure to antigen-presenting cells that express the peptide they recognize. Following immunization in the skin, this exposure will primarily occur in the:
Select one:
skin
muscle
lymph node
spleen
blood
lymph node
59
Positive selection occurs in the thymus and ensures that:
Select one:
T cells can recognize self MHC
T cells express either CD4 or CD8
T cells recognize foreign antigen
T cells can recognize costimulatory molecules
T cells do not recognize self-antigen
T cells can recognize self MHC
60
CD8 T cells have several mechanisms that can lead to lysis of target cells. Which of the following is not one of them?
Select one:
production of IFN-γ
perforin and granzyme induced killing
Fas-FasL interactions
release of lytic enzymes
production of TNF
production of IFN-γ
61
Naïve CD4 T cells can differentiate into different types of effector T cells. What cytokine promotes increased development of Th1 cells?
Select one:
IFN-γ
IL-4
IL-12
IL-17
IL-10
IL-12
62
What cytokine promotes the development of Treg cells?
Select one:
IL-10
IL-17
TGF-β
IL-6
IFN-γ
TGF-β
63
CD4 T cells recognize peptides by antigen-presenting cells because the antigen-presenting cells express:
Select one:
Class I
Class II
CD80
Surface bound Ig
all of the above
Class II
64
Cytokines act on cell surface receptors that signal cells by:
Select one:
a. phosphorylation of residues on the receptor and on STATS by JAK kinases, after which STATs dimerize and bind enhancer regions in the genes induced by the cytokines
b. internalization of the cytokine receptor, leading to JAK kinase dependent phosphorylation of STATS, which then dimerize and bind enhancer regions in the genes induced by the cytokines
c. phosphorylation of residues on the receptor and on STATS by JAK kinases, which activates NF-kβ, leading to transcription of genes induced by cytokines
d. phosphorylation of residues on the receptor, which then leads to dimerization or polymerization of the receptors, phosphorylation of STATS by JAK kinases, after which STATs dimerize and bind enhancer regions in the genes induced by the cytokines
e. all of the above
a. phosphorylation of residues on the receptor and on STATS by JAK kinases,
after which STATs dimerize and bind enhancer regions in the genes induced by the cytokines
65
What cytokine is particularly important in promoting the recruitment of neutrophils?
Select one:
IL-17
IL-4
IL-2
IL-10
TNF
IL17
66
Superantigens are considered dangerous because they activate many T cells, leading to uncontrolled cytokine release. Their ability to activate so many T cells is because:
Select one:
they are recognized by antibodies that bind to the T cell receptor
they are produced by bacteria in very high quantities
they can bind to both Class I and Class II and a conserved region of the T cell receptor
they bind to Class I and a conserved region of the T cell receptor
they bind to Class II and a conserved region of the T cell receptor
they bind to Class II and a conserved region of the T cell receptor
67
In order for a CD8 T cell to kill a virus-infected cell the infected cell only needs to express:
Select one:
Class I containing peptide recognized by the T cell receptor
Class I containing peptide recognized the T cell receptor and either CD80 or CD86
CD80 or CD86
Perforin and granzyme
Class I and Class II containing a viral peptide
Class I containing peptide recognized by the T cell receptor
68
Which of the following is true for IFN-γ?
Select one:
IFN-γ is produced by Th2 cells and promotes increased IgE responses
IFN-γ is produced by CD8 T cells and promotes increased cytolysis
IFN-γ is produced by macrophages and leads to increased killing of tumor cells
IFN-γ is produced by B cells and induced macrophage activation
IFN-γ is produced by Th1 cells and induces macrophage activation
IFN-γ is produced by Th1 cells and induces macrophage activation
69
When T cells leave the thymus they are able to function because they:
Select one:
are MHC restricted and express CD19
have differentiated into either a Th1, Th2 or Th17 cell effector T cell
are MHC restricted and express CD80 or CD86
are MHC restricted and express a T cell receptor
all of the above
are MHC restricted and express a T cell receptor
70
CAR-T cells are revolutionizing the treatment of some forms of cancer. These T cells are created by genetically manipulating a patient’s T cells so that they are better able to kill tumor cells. This manipulation involves:
Select one:
Modifying the cells so they constitutively produce Tumor Necosis Factor (TNF)
Modifying the cells so they express a T cell receptor (TCR) that recognizes a tumor antigen
Modifying the cells so they express an immunoglobulin that recognizes a tumor antigen
Modifying the cells so they constitutively produce anti-IL-10 antibodies
Modifying the cells so they constitutively produce IL-12
Modifying the cells so they express an immunoglobulin that recognizes a tumor antigen
71
Which T cell subset is most likely to promote an allergic reaction?
Select one:
Th2
Treg
CD8
Th1
Th17
Th2
72
When the T cell receptor binds to a peptide-Class II complex, it might not always induce T cell activation and proliferation. This could be due to:
Select one:
the peptide-Class Il expressing cell does not express CD28
the peptide-Class II expressing cell does not express CD80 or CD86
the T cell does not express CD80 or CD86
the T cell does not express CTLA-4
all of the above
the peptide-Class II expressing cell does not express CD80 or CD86
73
The Major Histocompatibility Complex encodes genes for Class I and Class II, which are critical for presenting antigen to T cells. One of the reasons Class I and Class II molecules can present so many peptides is because:
Select one:
a. there are two different genes, Class I and Class II that can present peptides
b. Antigen presenting cells express costimulatory molecules that promote T cell responses
c. there are multiple alleles at each single genetic locus coding Class I and Class II genes
d. there is clonal selection of T cells following antigen presentation
e. there is random recombination of the T cell receptor
c. there are multiple alleles at each single genetic locus coding Class I and Class II genes
74
Which cytokine listed is most associated with suppressing immune responses?
Select one:
TNF
IL-4
IL-2
IL-10
L-12
IL-10
75
F
F
T
F
T
76
77
kill bacteria
78
key features of cell surface vs endosomal localized TLRs
79
isotype switching
changes only the constant region of the Ig
80
phagocytosis and production of cytokines
81
antibody neutralization
82
\_\_\_ is the main Ig in primary antibody responses
IgM
83
84
+ selection occurs where
thymic cortex
85
how can T cells recognize so many peptides?
random recombinatio
86
87
MHC has evolved to prevent pathogen : one way:
several MHC molecules in each individual
88
AIRE is critical for
negative selection in the thymus
89
helminth infection
IL4
90
vaccine for intracellylar bacterial infection, what cytokine is important
IL12→ Th1 i\> killer
91
what determines the function of CD4 T cells responding following an infection
innate immune response
92
in order for CD8T cells to lyse, the target must :
express peptides recognized by the CD8 T cell
93
Th17 is important for
enhance the neutrophil response to fungal infections
94
IFN gamma is made by
T cells
95
IFN gamma does:
upregulating Class II
promote IgG2a isotype
activation of macrophages
(DOES NOT PROMOTE CD4 TH17 DEVELOPLEMT)
96
what cytokine supresses the immune response
il10
97
what cytokine promotes fever
IL1
98
what cell produce IL4
T cells
99
IL10 is produced by
TH2, TH1, T reg
100
CD4 T cell s differentiate into functionally distinct T cells when
they are exposed to different cytokines
101
what happens to the T cell poop once an immune response has elimated a pathogen?
die, some become memory
102
FHT cells are critical for the production of Ab by B cells, what set of cytokines are important?
IL21, IL4, IFN gamma
