Immunology Flashcards
1
Q
What factors stimulate monocyte differentiation into macrophages?
A
M-CSF
GM-CSF
2
Q
What factors influence development of dendritic cells from CD34+ stem cells?
A
GM-CSF
SCF
TNF-a
IL-4
TGF-B1
3
Q
What is the common progenitor cell of histiocytes?
A
CD34+ stem cells
4
Q
What type of adhesion molecule is expressed by all leukocytes?
A
Beta 2 integrins (CD11/CD18)
5
Q
What type of beta-2 integrin is expressed by Langerhans cells and interstitial dendritic cells?
A
CD11c
6
Q
What beta-2 integrin is expressed by macrophages?
A
CD11b (and CD11d by macs in spleen/bone marrow)
7
Q
What is expressed on the cell surface of Langerhans cells?
A
C-type lectin
Langerin
8
Q
What tissue does not contain interstitial dendritic cells?
A
Brain
9
Q
What markers are expressed by interstitial dendritic cells in the skin?
A
CD1a
CD11b
CD11c
MHC class II
CD90 (Thy-1)
10
Q
What are the only cells that can activate naive T-cells?
A
Dendritic cells
11
Q
Where are classical dendritic cells found?
A
Dermis
12
Q
Name 4 stimulators of type 1 classical dendritic cells
A
dsRNA (TLR3)
LPS (TLR4)
flagellin (TLR5)
nucleic acids (TLR7/9)
13
Q
What do type 1 classical dendritic cells express on their surface once activated?
A
MHC I
14
Q
What cytokine do type 1 classical dendritic cells secrete once activated?
A
IL-12
15
Q
What 2 cytokines suppress IFN-gamma production in the hair follicle and account for immune privilege in the follicle?
A
alpha-MSH
TGF-B1
16
Q
What factors stimulate type 2 classical dendritic cells?
A
IL-10
TGF-a
histamine
PGE2
parasitic worms
LPS
17
Q
Where are plasmacytoid dendritic cells found?
A
Bone marrow
Blood
Lymphoid organs
18
Q
What are the primary stimulators of plasmacytoid dendritic cells?
A
viral nucleic acids
19
Q
What cytokine is secreted in large amounts by plasmacytoid dendritic cells?
A
IFN-a (type I interferons)
20
Q
What cells contain Birbeck granules?
A
Langerhans cells
21
Q
What cytokines encourage Langerhans cells to migrate from the epidermis to the lymphatics?
A
TNF-a
IL-1Beta
22
Q
Where are Merkel cells found?
A
Tylotrich pads
HF bulge
23
Q
What happens to immature dendritic cells if they do not encounter antigens within a few days?
A
They die
24
Q
What stimuli cause immature dendritic cells to mature?
A
IL-1
TNF-a
PAMPs
DAMPs
25
What type of MHC are exogenous antigens attached to?
MHC class II
26
What type of MHC are endogenous antigens attached to?
MHC class I
27
What type of T-cells are activated by IL-12 secretion from dendritic cells?
Th1
28
What type of T-cells are activated by IL-1 and IL-6 secretion from dendritic cells?
Th2
29
What TLRs are involved in dendritic cell activation of Th1 cells?
TLR3
TLR4
TLR5
TLR7
TLR9
30
What TLRs are involved in dendritic cell activation of Th2 cells?
TLR1
TLR2
TLR6
31
What cytokine secreted by dendritic cells will activate Th17 cells?
IL-23
32
What type of T-cell will develop when IL-12 is absent?
Th2
33
What type of T-cell will develop when IL-12 is present?
Th1
34
What are the 3 mechanisms of immune tolerance by dendritic cells?
T-cell anergy
Clonal deletion
Induction of Tregs
35
What are the IHC markers for Langerhans cells in dogs?
CD1c
CD11c
CD80
MHC-II
36
What is the relationship between # of Langerhans cells and atopy?
Langerhans cells are increased in dogs with atopy
37
What type of immunity is reliant on complement?
Innate
38
What IHC markers are expressed by T helper cells?
CD4+ (CD3+, CD8-)
39
What marker is expressed by cytotoxic T-cells?
CD8+ (CD4-, CD3+)
40
What factor is essential for mast cell development?
Stem cell factor (c-kit ligand)
41
Which MHC molecule presents antigens to CD4+ T-cells?
MHC II
42
Which MHC molecule presents antigens to CD8+ T-cells?
MHC I
43
What IHC markers are expressed by Tregs?
CD3+
CD4+
CD25+
FoxP3+
44
What IHC markers are expressed by NK cells?
CD3+
CD16+
CD56+
45
What is the function of Tregs?
Suppress function of other T-cells
46
What marker is expressed by memory B-cells?
CD27
47
What type of T-cell are Th17 cells?
CD4+ (T-helper cell)
48
What type of T-cell are Th1 cells?
CD4+ (T-helper cell)
49
What type of T-cell are Th2 cells?
CD4+ (T-helper cell)
50
What is the site of maturation of B-cells?
Bone marrow and spleen
51
What is the site of maturation of T-cells?
Thymus
52
What type of adhesion molecule is responsible for low-affinity adhesion of circulating WBC to endothelial cells?
Selectins
53
What selectins are expressed by endothelial cells?
E-selectin
P-selectin
54
Which endothelial cell selectin is stored in granules and rapidly expressed in response to histamine?
P-selectin
55
What selectin is produced in response to IL-1 and TNF during infection?
E-selectin
56
What is the major ligand for P-selectin expressed by circulating leukocytes?
Sialyl Lewis X
57
What type of selectin is expressed on leukocytes?
L-selectin
58
Which chemokines recruit neutrophils?
CXCL1
CXCL8 (IL-8)
59
What allows for high-affinity binding of leukocytes to the endothelium during rolling?
Chemokines on endothelial cells binding to receptors on leukocytes
60
What ligand binds to integrin VLA-4 on on leukocytes?
VCAM-1 (on endothelial cells)
61
What ligand binds to integrins LFA-1 and Mac-1 on leukocytes?
ICAM-1 (on endothelial cells)
62
What type of junction must be disrupted in order for leukocytes to leave the blood and enter tissue?
Adherens junctions between endothelial cells
63
What chemokine receptors are expressed by neutrophils to allow for chemotaxis?
CXCR1
CXCR2
64
What chemokine receptor is expressed by monocytes to allow for chemotaxis?
CCR2
65
What chemokine is produced by tissue cells to recruit monocytes to tissue?
CCL2 (binds to CCR2 on monocytes)
66
What cell wall lipid serves as a PAMP for gram-positive bacteria?
Lipoteichoic acid
67
What cell wall lipid serves as a PAMP for gram-negative bacteria?
LPS
68
What are DAMPs?
endogenous molecules released by damaged/dying cells
69
What is the term for the class of receptors that recognize PAMPs and DAMPs?
PRRs (pattern recognition receptors)
70
What TLR do motile bacteria bind to?
TLR5
TLR11
(flagellin binding)
71
What TLR binds to dsRNA?
TLR3
72
What TLRs binds to ssRNA?
TLR7
TLR8
73
What TLRs are activated by heat shock proteins and HMGB1?
TLR2
TLR4
74
Which TLRs are expressed on the plasma membrane and sense extracellular PAMPs?
TLR1
TLR2
TLR4
TLR5
TLR6
TLR11
TLR12
75
What TLRs are expressed within cells on the ER and endosomal membranes?
TLR3
TLR7
TLR8
TLR9
TLR10
TLR13
76
What protein in the endoplasmic reticulum is essential for TLRs to localize to endosomes?
UNC-93B (deficient individuals are susceptible to viral infections)
77
What is one of the primary transcription factors that is activated when a TLR is bound?
NF-kB
78
Which TLR is NOT involved in the activation of NF-kB?
TLR3 (it activates type I interferons)
79
What 3 type of PRRs are present in the cytosol rather than on cell membranes?
NOD-like receptors
RIG-like receptors
cytosolic DNA sensors
80
What TLR recognizes DNA viruses?
TLR9 (+/-TLR3)
81
What TLRs recognize protozoa?
TLR9
TLR11
TLR12
82
What TLR regulates TLR2 responses and suppresses inflammation?
TLR11
83
What TLRs have been associated with Leishmania disease progression in dogs?
TLR2 upregulation
TL4 downregulation
TLR7 downregulation
TLR9 downregulation
84
What type of lymphocytes predominate in generalized demodicosis?
CD8+
85
What do RIG-like receptors sense?
Viral RNA
86
What do C-type lectins recognize?
Microbial carbohydrates
87
What type of C-type lectin is expressed by Langerhans cells?
Langerin (CD207)
88
What does TLR4 recognize?
LPS
89
What does TLR5 recognize?
Bacterial flagellin
90
What does TLR1 recognize?
Bacterial lipopeptides
91
What does TLR2 recognize?
Bacterial peptidoglycan
92
What does TLR3 recognize?
dsRNA
93
What does TLR6 recognize?
bacterial lipopeptides
94
What does TLR7 recognize?
ssRNA
95
What does TLR8 recognize?
ssRNA
96
What does TLR9 recognize?
CpG DNA
dsDNA
97
What does TLR11 recognize?
Profilin
Flagellin
98
What does TLR12 recognize?
Profilin
99
What does TLR13 recognize?
Unmethylated bacterial RNA
100
What cells of the skin are the most versatile sensors of PAMPs and DAMPs?
Dendritic cells
101
What cytokine is produced by ILC1s (innate lymphoid cells)?
IFN-gamma (intracellular microbe defense)
102
What transcription factor is expressed by ILC1s?
T-bet (similar to Th1 cells)
103
What cytokines are produced by ILC2s (innate lymphoid cells)?
IL-5
IL-9
IL-13
(helminth defense)
104
What transcription factor is expressed by ILC2s?
GATA-3 (like Th2 cells)
105
What cytokines are produced by ILC3s?
IL-22
IL-17
(extracellular bacteria and fungi defense)
106
What IHC markers would denote an NK cell?
CD3-/CD56+
107
What is the primary cytokine produced by NK cells?
IFN-gamma
108
What proteins are contained within NK cell granules and are released when NK cells are activated?
Perforin
Granzymes
109
Which cytokines activate NK cell-mediated killing?
IL-12
IL-15
110
An NK cell recognizes MHC class I on a potential target. Is the target cell likely to be killed?
No--the NK cell will be inhibited so that killing does not occur (normal cells should express MHC class I)
111
Which part of complement is triggered by mannose-binding lectin?
Lectin pathway
112
What part of complement is triggered by the binding of C1q to the Fc portion of microbial antibodies?
Classical pathway
113
What part of complement is triggered by the recognition of microbial surface structures by C3?
Alternative pathway
114
What proteins make up the membrane attack complex?
C5b
C6
C7
C8
C9
115
What protein serves as an opsonin in the complement cascade?
C3b
116
What pathway of complement is antibody-mediated?
Classical pathway
117
What antibody is most efficient at complement-binding?
IgM (>IgG)
118
What is the function of the membrane attack complex?
Cause cell lysis
119
What is the function of complement?
Opsonization
Promote phagocytosis
Stimulate inflammation
120
Name the 3 most important inflammatory cytokines of the innate immune system.
TNF-a
IL-1
IL-6
121
What are the main cell types that produce TNF-a?
Macrophages
Dendritic cells
122
IL-12 and IFN-gamma are secreted during antigen presentation to a naive T-cell. What cell is it likely to become?
Th1 cell
123
IL-1, IL-6, and IL-23 are secreted during antigen presentation to a naive T-cell. What cell is it likely to become?
Th17 cell
124
IL-4, IL-25, IL-33, and TSLP are secreted during antigen presentation to a naive T-cell. What cell is it likely to become?
Th2 cell
125
What is the effect of IL-6 on B-cells?
Promotes antibody production
126
What cytokine inhibits macrophage and dendritic cell activation (i.e. anti-inflammatory)?
IL-10
127
What is the term for the antigen-binding portion of an antibody?
Fab region
128
What part of an antibody molecule is involved in effector functions?
Fc region
129
Which 2 antibodies are involved in complement activation?
IgG
IgM
130
What is the function of MHC molecules?
Bind and display peptides to be recognized by CD4+ and CD8+ T-cells
131
What chemokines attract APCs into LN for presentation to T-cells?
CCL19
CCL21
(bind to CCR7 receptor on dendritic cells)
132
What type of MHC molecule is expressed on almost all nucleated cells?
MHC class I
133
What is the main cytokine that stimulates expression of MHC class II?
IFN-gamma
134
What are the 4 major subsets of CD4+ T-cells?
Th1
Th2
Th17
Treg
135
What is the defining cytokine of Th1 cells?
IFN-gamma
136
What is the major function of Th1 cells?
Macrophage activation
137
What are the defining cytokines of Th2 cells?
IL-4
IL-5
IL-13
138
What are the main effector functions of Th2 cells?
Mast cell and eosinophil activation
139
What are the defining cytokines of Th17 cells?
IL-17
IL-22
140
What are the major functions of Th17 cells?
Neutrophil recruitment and activation
141
What chemokine receptors are expressed in high levels by Th1 cells (but not Th2)?
CXCR3
CCR5
142
What chemokine receptors are expressed in high levels by Th2 cells?
CCR3
CCR4
CCR8
143
Which chemokine receptor is expressed in high levels by Th17 cells and what is its ligand?
CCR6
Binds to CCL20
144
What type of organism drives Th1 cell development?
Intracellular microbes
145
What type of organism drives Th2 cell development?
Helminths
146
What type of organism drives Th17 cell development?
Fungi
Some bacteria
147
Which ligand is present on Th1 cells and serves to activate macrophages to kill intracellular bacteria?
CD40L
148
What antibody is likely to be produced by a B-cell when stimulated by IL-4?
IgE
149
What cytokine is the primary activator of eosinophils?
IL-5
150
What cytokines are important for CD8+ cell differentiation?
IL-2
IL-12
IL-15
IL-21
type I interferons
151
What are the major cytotoxic proteins in granules of CD8+ T-cells?
Granzymes
Perforin
(same as NK cells)
152
What are the 2 mechanisms of cytotoxic T-cell-mediated killing?
Perforin and granzymes
Fas and FasL
153
What is the primary cytokine produced by CD8+ T-cells?
IFN-gamma
154
What complement pathways are activated by extracellular bacteria?
Alternative
Lectin (if the bacteria express mannose on their surface)
155
What type of bacterial infection requires cell-mediated immunity: intracellular or extracellular?
Intracellular
156
What is generated by COX-2?
Prostaglandins
157
What combination of cytokines is responsible for sickness associated with inflammation (fever, lethargy, malaise)?
TNF-a and IL-1
158
What cytokine is a "master regulator" that triggers and maintains allergic inflammation at barrier surfaces?
TSLP
159
What type of cell does IL-25 attract?
Eos
160
What cytokine family is IL-31 a member of?
IL-6
161
Which histamine receptor plays a major role in IL-31 release?
H2
162
What is CXCL8 also known as?
IL-8
163
What 2 chemokines are major neutrophil attractants?
CXCL8
CXCL2
