Block 1 Dr. Smith Immunology Flashcards
(159 cards)
1
Q
Immune cell that matches with CD3
A
All T cells
2
Q
Immune cell that matches with CD 4
A
T helper cells
3
Q
Immune cell that matches with CD19
A
B cells
4
Q
Immune cell that matches with CD20
A
B cells
5
Q
Immune cells that matches with CD34
A
Pluripotent hematopoietic stem cells
6
Q
Immune cell that matches with CD45
A
All leukocytes
7
Q
Immune cell that matches with CD56
A
NK cells
8
Q
Immune cell that matches with CD8
A
Cytotoxic T cells
9
Q
What is the equivalent of CDR protein marker
A
Hyperviariable region
10
Q
MHC is the same as :
A
HLA
11
Q
CD54 is the same as :
A
CD40L
12
Q
B7.1/B7.2 →
A
CD80/86
13
Q
CR2 →
A
CD21
14
Q
Most immune cells descend from what?
A
CD34+ multipotent stem cells in the bone marrow.
15
Q
In general, IL-3 goes along what lineage?
A
Myeloid
16
Q
In general, IL-7 goes with what lineage?
A
Lymphoid
17
Q
Once in the lymphoid pathway, IL-7 alone will result in production of what immune cell ?
A
NK cell progenitor
18
Q
IL-7 & IL-2 together will result in production of what immune cell?
A
T-cell
19
Q
IL-15 will turn the progenitor cells into?
A
NK cell
20
Q
IL-4 results in the production of ?
A
B cells
21
Q
M-CSF results in differentiation of ?
A
Mononcyte progenitors
Macrophages, monocytes, dendritic cells
22
Q
G-CSF results in differentiation of ?
A
Granulocyte progenitors
Neutrophils, basophils, eosinophils
23
Q
B lymphocytes, T lymphocytes and NK cells come from what lineage?
A
Lymphoid
24
Q
Myeloid linage gives rise to :
A
Granulocytes, monocytes and some dendritic cells
25
Innate immune cells include :
Neutrophils
Macrophages
Dendritic cells
26
2 innate immune cells that play a role in adaptative immunity also?
APC cells such as macrophages and dendritic cells.
27
Class I MHC takes stuff from inside cells & interact with ?
CD8
28
Class II MHC takes stuff from outside cells and interacts with ?
CD4
29
What are naive lymphocytes?
Adaptative immune cells that have not encountered their antigen yet.
30
Innate immune cells that are phagocytes:
Neutrophils
Macrophages
| Major players in early inflammatory response
31
Main difference between a macrophage and a monocyte?
Monocyte circulate in the blood
Macrophage are tissue resident cells
32
This granulocyte is the first line of defense against invaders:
Neutrophils
33
Main mechanism neutrophils kill?
Oxidative burst
| Toxic oxygen-derived products
34
Production of Lactoferrin by neutrophils affect bacteria in what way?
Lactoferrin binds iron which is necessary for survival of bacteria.
35
What are NETs?
Neutrophil extracellular traps (neutro barf up the content of the nucleus if the thing is too big to phagocytose them)
| E.g. Fungi, biofilms
36
Tissue resident macrophages come from where ?
Fetal yolk sac (early on in life)
37
Difference between M1 & M2 macrophages
M1 secrete cytokines and are main drivers of the inflammatory response
M2 usually show up at the end to ''clean up everything''
38
Main mechanism macrophages use as a defense?
NO production
39
What disease results from disfunctional NADPH enzyme of the oxidative burst cascade?
Chronic granulomatous disease (CGD)
## Footnote
Severe opportunistic infections with catalase + bacteria
40
What test is used to diagnosis disfunctional oxidative burst in neutrophils?
NBT test
| Usually it should turn blue (oxidative burst reduces the dye to blue)
## Footnote
If it does not turn blue, the test is negative.
41
Less servere version of CGD where you have NAPDH oxidase but lack another important enzyme to complete oxidative burst?
Myeloperoxidase deficiency
| NBT test would be positive (normal) in this case
42
Disease resulting from no LYST protein (no phagolysosome formation) with partial albinism as a feature and giant inclusion bodies seen in WBC in microscopy?
Chediak-Higashi syndrome.
43
Mast cells are part of innate or adaptative immune system?
Innate
44
Cells that have receptors for IgE on them and produce a local inflammatory response when they degranulate their histamine?
Mast cells
45
Short lived cells that contain MBP in their granules and release them via exocytosis to kill parasites ?
Eosinophils
46
Langerhans cells are example of what type of immune cell that is very good at capturing antigens and showing them off to T cells?
Dendritic cell
47
Ringleaders of the transition from the innate to adaptative immune system?
Dendritic cells.
48
Represent 15% of the lymphocyte population
B cells
49
T cells represent what % of lymphocyte population?
80%
50
Are not necessarily MHC restricted
Can be phagocytic
Can present antigen
B cells
51
B cells can become either :
Plasma cells
Memory B cells
52
Can be either killers, regulators or helpers
T lymphocytes
53
Which of the following components of the adaptive immune system causes lysis of virally infected cells and the release of cytokines?
CD8+ cytotoxic T cell
54
Is the complement response innate or adaptative ?
Innate
## Footnote
Complement is one of the soluble effector molecules of our innate immunity. One of its main job is to provide a mechanism by which adpatative immune molecules (antibodies) mediate the killing of the pathogen.
55
Main 3 functions of Complement?
1. Opsonization of microbes
2. Recruitment of phagocytes to site of infection
3. Kill microbes
## Footnote
Complement tags the pathogen, so that macrophages and neutrophils can come and do their jobs. Thats how they recruit phagocytes to the site of infection.
56
Complement proteins are made in:
Liver
57
C1, C2, C3 and C4 are involved in earlier or later responses ?
Earlier
58
C5, C6, C7, C8 & C9 are involved in earlier or later responses ?
Later
59
Which subunit of a complement is involved in anaphylaxis ?
a subunit
60
Which subunit of the complement, when cleaved, is more likely to act as an opsonin ?
b subunit
61
What are the 3 ways you can activate a complement pathway?
Classical pathway
MBP pathway
Alternative pathway
62
Is C5a more or less inflammatory than C3a?
Way more
63
C5b-C9 complex is responsible for making :
MAC complex
| Membrane attack complex
64
Which Complement is responsible for activation of opsonization, phagocytosis/clearance and b-lymphocyte activation?
C3
65
What complement pathway requires presence of existing antibodies to be kicked off ?
Classical pathway
66
What are the 2 immunoglobulins involved in activation of the classical pathway ?
IgM and IgG
| ** IgM to a much greater extent.
## Footnote
IgA, IgD and IgE do not activate the pathway
67
IgM and IgG interact with which protein to kick off the classical pathway ?
C1q
68
Is the classical pathway he fastest way to activate the complement system ?
No.
69
C4bC2b represents ?
C3 convertase
70
What is the role of C3 convertase?
Cleave C3, forming C3a and C3b.
C3 convertase + C3b together will form C5 convertase.
71
In the case that antibodies are not present, what are other molecules that recognize PAMPs that could help kick off the complement system?
Mannose binding lecitin (mannose on surface of microbes)
Ficolin (NAGs)
CRP (complement binding protein)
| All of these can act like C1q
72
What regulating molecule prevents accumulation of C1 on cells that without it would result in hereditary angioedema?
C1 inhibitor (C1 INH)
| Prevents accumulation of enzymatically active C1r2s2
73
Recombinant C1 elastase inhibitor could help treat what condition ?
Hereditary angioedema
| People who lack C1 inhibitor
74
Which pathway runs continuously and spontaneously at low levels in the blood plasma ?
Alternative pathway
## Footnote
Innate immune response that is the most rapid to react i.e. as soon as a pathogen enters the body.
75
C3, factor B and D refer to what pathway of complement activation ?
Alternative
## Footnote
C3 in the blood gets hydrolysed, facor B and D bind it, cleaved to form C3b that just floats around and is ready to bind any invader's cell membrane.
76
C3bBb refers to ?
C3 convertase of alternative pathway
| It cleaves C3 in the alternative pathway.
77
If someone lacks factor B, what happens?
You are not making C3 convertase in the alternative pathway.
| No inflammatory reponse is induced by this pathway.
78
Factor I & H are ?
Regulators of C3 convertase in the alternative pathway.
79
MCP aka CD46, CR1 and DAF refer to ?
regulatory proteins expressed in mammalian cells that breakdowm complement products on the cell membrane.
| They act as cofactors for factor I & H.
## Footnote
DAF works in all complement pathways !
80
Deficiency in DAF leads to what condition ?
| DAF (Decay Accelerating Factor)
Paroxysmal nocturnal hemoglobinuria
## Footnote
They regulate the complement system. Without it, too much complement activation can occur. RBC are very susceptible to this and lyse easily.
81
C3b is super important for :
Opsonization
82
How does the MAC complex help with destruction of invaders ?
Pokes wholes in the phospholipid membrane.
## Footnote
MAC requires the presence of an accessible phospholipid membrane.
83
What organisms would be resistant to the MAC attack ?
Bacteria with polysaccharide capsules
Gram + bacteria
Acid-fast bacteria
Non-enveloped viruses
84
All mammalian cells express CD59 (protectin). What is it's role?
Prevents C9 from forming a complex i.e prevents formation of MAC complex on our cell membranes.
85
People who lack CD59 would have what condition?
Paroxysmal nocturnal hemoglobinuria
86
What organisms are susceptible to MAC ?
Enveloped viruses
Gram negative bacteria
| Both have accessible phospholipid membranes.
87
Binds to Complex 1 and removes it from C1q?
| Deficit would lead to hereditary angioedema
C1 inhibitor
88
Control protein of the alternative pathway that binds C3b displacing Bb :
Factor H
89
Factor that is involved in the 3 complement pathways that cleaves C3b and C4b
| Serine protease
Factor I
90
Only control protein after the C5 step that prevents the formation of MAC and that would result in paroxysmal nocturnal hemoglobinuria if dysfunctional :
CD59 (protectin)
91
Macrophages and neutrophils have this receptor to recognize opsonized cells and binding stimulates phagocytosis ?
CR1
92
B cells have what complement receptor which helps activating them ?
CR2 (CD21)
93
What are DAMPs (alarmins)
Damage associated molecular patterns (molecules within us that can generate an innate immune response and thus inflammation).
## Footnote
E.g. stress induced proteins, crystals, nuclear proteins...
94
NLR (Nod like receptors) aka NODs are a type of pattern recognition receptor that recognize what?
Bacterial peptidoglycans when the bacteria have made their way into the cell.
95
RLR or Rig like receptors recognize ?
Double stranded RNA and DNA-RNA combos in the cytoplasm.
96
Cytosolic DNA sensor (CDS), a pattern recognition receptor, binds what?
Microbial double stranded DNA that floats around in the cytosol.
97
Dimers
TLR1:TLR2
&
TLR2:TLR6
recognize ?
Bacterial lipopeptides
98
TLR2 recognizes ?
Bacterial peptidoglycans
99
TLR3 recognizes?
Endosomal double stranded viral RNA
100
TLR7 and TLR8 recognize ?
Endosomal single stranded viral RNA
101
TLR9 recognizes ?
Endosomal unmethylated CpGs
102
Following binding of the TLR, activation of the transcription factor NFkB leads to what ?
Production of inflammatory cytokines
Acute inflammation
Stimulation of adaptative immune response
103
IRF (interferon response factor) leads to production of proinflammatory cytokines in what type of immune response ?
Anti-viral response
104
IFN a & IFN b are type 1 interferons involved in what immune response ?
Antiviral
105
Direct roles of type 1 interferons
Inhibits viral protein synthesis
Degradation of viral RNA
Inhibits viral gene expression and viron assembly
It also stimulates non infected cells to raise defenses
106
Induces resistance to viral replication in all cells
Increases MHC class I gene expression and antigen presenting in all cells
Activate dendritic cells and macrophages
Activate NK cells to kill virus-infected cells
IFN-a & IFN-b
107
Cytosolic receptors associated with gut immunity?
NODs
| Polymorphism associated with IBD
108
NOD2 recognizes what specific PAMP?
NAMs
109
Cytokine signaling uses what pathway to modulate expression of specific cytokine responsive genes in the nucleus?
JAK-STAT
110
What molecule is reponsible for directing the immune cells to the site of infection?
| Activation of endothelial cells
Chemokines
## Footnote
Signaling through chemokine receptor induces expression of high affinity integrin.
P & E selectins expressed by endothelial cells bind a CHO side chain on PMN. Integrin (LFA-1) on the PMN and adhesion molecule such as ICAM-1 on the endothelial cell binding creates a conformational change in LFA-1 which is induced by **IL-1** secreted by cells in the inflamed tissue. CD 31 at endothelial cell junctions mediates the diapedesis of the PMN.
111
As an immediate response to injury, epithelial cells make :
Defensins (disrupt microbial cell membranes)
Cathelicidins (bind LPS)
112
What cells can be found in the dermis that provide a second line of defense ?
Mast cells and Macrophages
113
5 cardinal signs of inflamnmation ?
Redness
Heat
Swelling
Pain
Loss of function
114
What cells are first activated in response to trauma/injury/necrosis/infx or immune rx ?
Mast cells
115
What is the content of mast cell degranulation?
Pro-inflammatory cytokines
(Histamine, Heparin, Prostaglandins, leukotrienes, PAF) basically vasoactive compounds causing vasodilation up to a point where the vessels become leaky (transudate release).
| Histamine is involved with pain
Prostaglandins mainly with edema
## Footnote
PAF = platelet activating factor
116
Specific chemokine released by platelets that creates a chemotactic gradient for neutrophils extravasation.
CXCL8 (IL-8)
117
What is leukocyte Adhesion deficiency?
Group of disorders in which the leukocyte interaction with vascular endothelium is disrupted.
- Recurrent soft tissue bacterial infections
- Increased WBC counts
- No pus formation or effective wound healing
- Delayed umbilical cord detachement
118
3 pro-inflammatory cytokines produced by macrophages
IL-1, IL-6 & TNF a
| All 3 drive fever.
## Footnote
Also stimulate production of complement, activate adaptative immune response
119
Pro-inflammatory cytokine released by macrophage that induces acute phase protein production by hepatocytes (CRP):
IL-6
120
Platelets can secrete CXCL8 to recruit neutrophils & basophils to the site of infection. What other immune cell secretes this chemokine ?
Macrophages
121
IL-12 is a pro-inflammatory cytokine secreted by macrophages. What immune cell does it activate ?
NK cells
& Th1 cells
122
Binds phosphocholine on bacterial surfaces, acting as an opsonin and as a complement activator and which excess production may result in shock :
CRP
## Footnote
Mannose-binding lecitin binds to CHO on bacterial surfaces and also act as an opsonin and as a complement activator.
123
Are especially important in healing and interacting with adaptative immune cells in late stages of acute inflammation :
M2 macrophages
124
M2 macrophages release what **regulatory** cytokines?
IL-10 & TGFb
## Footnote
Switch to wound repair and collagen synthesis & fibrosis
125
It is the primary scavanger and repair cell in chronic inflammation.
Tissue macrophage
## Footnote
They clear tissue of the products of inflammation by action of phagocytosis coupled with lysosomal enzymes and set the stage for tissue repair.
126
Chronic, long term inflammation is controlled by what immune cell?
Macrophage
127
If not cleared, sites of chronic inflammation may turn into :
Granuloma
128
Tissue macrophages secrete IL-12 in response to bacteria which drives the production of which molecule important for effective killing of intracellular organism?
Th1 cells
(produce IFN gamma)
## Footnote
Th1 cell provide help to macrophages (thus this IL-12/IFNy pathway is a self-enhancing pathway).
129
Prolonged untreated inflammation would result in î of what type of immature cells ?
Band cells
## Footnote
Local acute inflammatory response -> secretion of IL-6 and TNF-a which signals the bone marrow to î M-CSF & C-GSF lineages to a higher rate for leukocytosis but after a while, production cant provide enough, so immature cells start being released in the blood.
130
IL-1 cytokine produced by macrophages in case of acute inflammatory response leads to activation of what specific cell?
Activate all T cells
131
Requirements to be an antigen ? i.e. to be able to evoke an immune response :
Foreignness
Molecule weight (> 1000 Da)
Degradability
Chemical complexity
132
Main difference between TCR and BCR :
TCR are MCH restricted (they require antigen presenting cells)
BCR are not MHC restricted (part of this receptor is an antibody which is located on the cell surface). B cell can recognize antigen in the wild.
133
Minimal size for immunogeneicty :
> 30 kD
| approx size of an allergen
## Footnote
Polysaccharides are > 100 kD so highly immunogenic and for proteins at least 30 kD is sufficient because we make better response against proteins than CHO. Under 30 kD, there could be possible immunogenicity, but the immonogens would need to be coupled with a bigger carrier.
134
What kind of response does polysaccharide immunogens produce ?
T-independent IgM response
| MHC independent
135
What kind of response does nucleic acids & phospholipids immunogens produce ?
low affinity T-independent IgM response
| MHC independent
136
Haptens produce what kind of immunologic response ?
Insufficient size to be immunogenic. They need a carrier.
| Haptens are basically epitopes
## Footnote
E.g. of haptens include hormones, lipids, simples sugars, chemicals such as most drugs (penicillin*).
137
Foreign proteins and glycoproteins (free or part of microbial or eukaryotic cell membranes) induce what kind of immunologic response ?
T-dependent humoral immunity antibody : IgG, IgA, IgE.
| MHC dependent
GOOD CLASS-SWITCH response
138
What are adjuvants ?
They enhance immune response by increasing the half life of the immunogen, by incresing local inflammation and improving processing and presenting by MHC. Basically, they act as a big ''pro-imflammatory envelop'' so that the immune system has a better chance of paying attention to the immunogen. The adjuvant itself is NOT an immunogen.
139
What is the purpose of carrier proteins?
They can be use as a conjugation molecule (to hapten for instance) in order for the potentially but too small immunogen to generate a response. This can also help prolonged the half life and create better IgG response for better memmory.
140
What is an epitope?
Specific region of the antigen that is recognized by the antibody or displaced on the surface of the MHC
141
B cells bind what king of antigen ?
Soluble
142
Can T cell bind soluble antigens ?
No
143
Which adaptative immune cell can bin protein antigen as well as polysaccharides antigens ?
B cells
144
Can only bind protein antigen and glycolipid antigens ?
T cells
145
What epitode propreties are requires for B cells to bind the antigen ?
Accessible
Hydrophilic
Mobile peptides (either linear or conformational)
146
What epitope propreties are required for T cells to bind the antigen ?
Short internal linear peptide
147
Which anatomical part of the antibody can bind the antigen ?
Fab portion
148
Which part of the antibody can be crystallized and refers to the bottom part of the antibody ?
Fc portion
149
Kappa chains and Lambda chains refer to :
Light chains in antibodies that are randomly attributed (60% kappa; 40% lamba)
150
What part of the antibody determines the class?
Heavy chains
## Footnote
5 classes of heavy chains : IgG (y) IgA (a) IgM (u), IgE (epsilon), IgD (delta)
151
Variable domains binds the :
Constant domain important for:
Antigen
Mediating secondary biological functions
152
What makes the antigen specific to a specific antibody ?
Hypervariable region (sequence variability is concentrated in 3 segments of both L and H chains variable regions).
| 6 unique hypervariable regions
12 in total (2 arms)
153
Why can only IgM and IgG activate the complement ?
C1q can only interact with CH2 domain in the hinge region of the heavy chains (Fc region) of the antibody and only IgG and IgM have that specific CH2 domain.
154
What is the hinge region?
Short span of AA between 1st and 2nd constant domains of the antibody rich in cystine and prolines. Provides felxibility of the molecule which makes it better at binding antigens.
## Footnote
Basically it links the Fab and Fc portion and allows binds of Ab to antigen in multiple directions.
155
The portion of the An that allows for interactio of the immune complexes with other cells ?
Fc portion
## Footnote
The Fc portion allows the innate and adaptative immune systems to interact with each other. Most cells (neutro, mast cells, macrophages, dendritic, etc) have Fc receptors on their cell membranes. This is another way you can get opsonization as these cells can recognize the bound Ab-antigen complex via this Fc receptor and internalize it and then present to the T cells. FcR can be activation or inhibitory (less common).
156
BCR is an example of what type of immunoglobulin expression ?
Transmembrane Ig
157
Secretory immunoglobulin:
IgA
| Breast milk
Gut immunity
158
Fc receptors are an exemple of what type of immunoglobulin expression?
Cell-bound (non transmembrane) Ig
| E.g. Mast cells (IgE receptors)
## Footnote
Not the Ab itself that is signaling, but the Fc receptor bound to the Ab that creates a response.
159
Provide a natural autoimmune mechanism for regulating Ab levels
Ig Idiotypes
| Idiotypes refers to the entire variable region or entire biding site
