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Immunology Test 1 > TEST 1 > Flashcards

TEST 1 Flashcards

1
Q

What Components would be used in an Extracellular Infection of the Mucosa?

A

Antibodies
Intraepithelial
PMNs Cells

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2
Q

True or False: Noninfectious foreign substances called antigens (Ags) can also elicit an immune response

A

True

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3
Q

Life Span of Neutrophil

A

Blood: Hours or a Few Days
Tissues: 1 to 2 days

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4
Q

Microbes able to survive in animals by growing extracellular being simply immersed in nutrients

A

Extracellular Microbes

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5
Q

Describe Mononuclear Phagocyte Cells

A

Monocytes and Resident Tissue Macrophages

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6
Q

Which immune cell mediates the earliest phases of. Inflammatory reactions

A

Neutrophils

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7
Q

What gives rise to cellular immunity?

A

T-Cell that is Ag stimulated

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8
Q

List the Cells that protect against helminthes and mediate reactions that cause allergic diseases

A

Mast Cells
Basophils
Eosinophils

** These cells have cytoplasmic granules filled with inflammatory and antimicrobial mediators

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9
Q

List all the cells of innate immunity

A

1) Neutrophil
2) Eosinophil
3) Basophil
4) Mast Cell
5) Monocyte
6) Macrophage
7) Dendritic Cell
8) Natural Killer (NK)

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10
Q

True or False: Neutrophils are short live and Resident Macrophages are long-lived

A

True

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11
Q

True or False: Mononuclear Cells play a central role in both innate and adaptive immunity

A

True

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12
Q

Steps in Functional Responses of Phagocytes

A

1) Chemokine-mediated recruitment of the cells from the blood and surrounding tissues to the sites of infection/inflammation
2) Receptor-dependent recognition of microbes and activation of phagocytes
3) Activated Phagocyte secrets cytokines/chemokines to promote and/or regulate immune responses
4) Formation of phagosome and ingestion of the microbes
5) Intracellular destruction of ingested microbes in lysosomes

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13
Q

Functions of Cytokines

A

1) Regulate growth and differentiation of all immune cells

2) Activate the effector functions of lymphocytes and phagocytes

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14
Q

True or False: Mast Cells, Basophils and Eosinophils are apart of only the innate immune response

A

False: Apart of both immunities

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15
Q

Function of Chemokines

A

Cell Migration and Movement

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16
Q

Why is it important for Mast Cells to be in close proximity to blood vessels that supply tissues exposed to the external environment

A

They regulate vascular permeability and modulate effector-cell recruitment without direct cell-cell contact via release of mediators

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17
Q

True or False: Antibodies recognize, neutralize, and target microbes for elimination

A

True

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18
Q

Cell is infected with a bacteria that is replicating in the cytoplasm. What Type of infection is it and What cells will act on this infection? How would it be different if a Mycobacteria infected a cell?

A

1) Intracellular Infection of the Cytoplasm
2) CTLs, NK Cells, T Cells, and Macrophages
3) Would be considered a Intracellular Vesicular Infection and only T Cells, NK Cells and Macrophages would act on this infection.

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19
Q

Epitope

A

Portion of an Ag molecule to which an antibody binds

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20
Q

Function of Cell-mediated Immunity

A

Killing of infected HOST cells to eliminate reservoirs of infection

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21
Q

What Humoral Components are used in a Blood or Lymphatic infection?

A

Antibodies
PMNs (Neutrophils)
Complement

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22
Q

Microbes invade and live and replicate intracellular within animal cells where they utilize host-cell energy

A

Intracellular Microbes

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23
Q

True or False: Cytokines can only be secreted and are only involved in the innate immune system

A

False: Cytokines can be secreted or membrane bound; They also involved in innate and adaptive immunity

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24
Q

Function of Humoral Adaptive Immunity

A

Principal defense mechanism against extracellular microbes and their toxins because secreted Abs can bind to these microbes and toxins and assist in their elimination

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25
Q

Collateral Damage

A

An immune response against microbes causing tissue damage

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26
Q

Which Cell controls CMI?

A

T Lymphocytes

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27
Q

Describe the tissue specific functions of Macrophages

A

1) Maintenance of tissue homeostasis via phagocyte clearance
2) Tissue immune surveillance.
3) Control of an innate immune response to infection
4) Antigen Presenting to T cell
5) Resolution of inflammation

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28
Q

True or False: Ags include proteins, Carbs, Lipids, and nucleic acids

A

True

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29
Q

What gives rise to Humoral Immunity and production of immunoglobulins

A

Development and maturation of B cells

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30
Q

An adult human is producing less than 1x10^11 neutrophils which cytokine may be deficient?

A

Granulocyte Colony-stimulating factor (G-CSF)

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31
Q

What are the Two Types of Adaptive Immunity

A

Cellular Immunity and Humoral Immunity

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32
Q

What Factor stimulates the mononuclear lineage

A

Monocyte/Macrophage colony-stimulating factor

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33
Q

Are NK cells apart of the innate or adaptive immune system

A

Innate

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34
Q

Draw the Origin of Blood Cells

A

Draw the Origin of Blood Cells

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35
Q

What are the primary lymphoid organs

A

Thymus and Bone Marrow

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36
Q

What are the Secondary Lymphoid Organs

A

Spleen
Lymph Nodes
Mucosa-associated lymphoid

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37
Q

What is the name of the stem cell that is common to all blood cells?

A

Common CD34+ Pluripotent Stem Cell

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38
Q

Naive Lymphocytes Life Span

A

1-3 months

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39
Q

What T Helper Cells express what protein?

A

CD4+

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40
Q

Function of T-Helper Cell

A

Provide help for B cell growth and differentiation

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41
Q

Cytotoxic T Lymphocytes Express What Protein

A

CD8

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42
Q

Function of cytotoxic lymphocytes

A

Recognize and kill virus-infected cells

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43
Q

What happens to T cells that are highly reactive to self-Ags?

A

Deleted by apoptosis

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44
Q

They ima

A

Slow-growing tumor that typically start in thymine epithelial cells.

***DOESNT spread beyond the thymus gland

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45
Q

Thymus Carcinoma

A

Aggressive cancer of thymine epithelial cells

**Spreads quickly

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46
Q

When are most thymomas/thymic carcinomaas diagnosed?

A

Between 40 and 60

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47
Q

True or False?

A

Thymoma/Thymic Carcinoma-associated immunodeficiencies are very rare

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48
Q

Leukemia

A

Overgrowth of immature blood cells leading to a shortage of normal white and RBCs and platelets

*Associated with infections (anemia and bruising)

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49
Q

Myeloproliferative Disorders

A

Overproduction of one type of blood cell

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50
Q

Multiple Myeloma

A

Abnormal Plasma Cells produce proteins that impair the development of normal blood cells causing anemia and leukopenia

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51
Q

Lymphoma

A

Cancer that develops in circulating blood lymphocytes after production in bone marrow

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52
Q

Name the places where lymphocytes don’t circulate

A

Eye
Brain
Testicles

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53
Q

Lymphocytes enter secondary lymphoid organs via what?

A

HEVs

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54
Q

How do Naive Lymphocytes renter the circulation?

A

Via Efferent lymph vessels that merge into the thoracic duct

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55
Q

Ag-activated B cell proliferates mature into what cells?

A

Plasma Cells or Memory Cells

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56
Q

Ag-Activated B cells primarily produce Abs against what type of microbes?

A

Extracellular Blood Microbes

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57
Q

Spleen Participates in immune responses against many types of _____ pathogens.

A

Blood-Born

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58
Q

The spleen in made up of T cell zone and B cell zone. Where are each of these located in the spleen?

A

T cell zone: Located centrally

B cell zone: Distributed around the T zone in tightly packed follicles

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59
Q

T cell zone of the spleen is also known as what?

A

Periarteriolar lymphoid sheath or PALS

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60
Q

Neutrophil Function

A

Early phagocytosis and killing of microbes

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61
Q

Macrophages

A

Efficient phagocytosis and killing of microbes secretion of cytokines that stimulate inflammation

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62
Q

NK Cell Function

A

1) Lysis of infected cells

2) Activation of macrophages

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63
Q

Circulating Effector Cells of Innate Immunity

A

Neutrophils
Macrophages
NK cell

64
Q

Circulating effector proteins of Innate Immunity

A

Complement
Mannose-binding lectin (collectin)
C-reactive protein (pentraxin)

65
Q

Complement Function

A

Killing of microbes
Opsonization of microbes
Activation of leukocytes

66
Q

Mannose-binding lectin (Collectin)

A

Opsonization of microbes

Activation of complement (Lectin pathway)

67
Q

C-reactive protein (pentraxin)

A

Opsonization of microbes

Activation of complement

68
Q

Cytokines of Innate Immunity

A

1) TNF, IL-1, Chemokines - inflammation
2) IFN-alpha and beta - viral infection
3) IFN-y - Macrophage activation
4) IL-12 - IFN-y production by NK cells and T cells
5) IL-15 - Proliferation of NK cells
6) IL-10, TGF-B - Control of inflammation

69
Q

Two Types of Toll-like Receptors, TLRs

A

1) Cell Surface: TLR-1,2,4,5,6

2) Endosomal: TLR-3,7,8,9

70
Q

List and Describe the Toll-like receptors found associated with NK cells.

A

1) TLR3 - Double-stranded viral RNAs

2) TLR 7 and 8 - Single-Stranded viral RNAs

71
Q

List and Describe the Toll-like receptors found associated with Intestinal Epithelium

A

TLR5 - Flagellin

72
Q

TLR1:TLR2 heterodimer ligands are Lipopeptides and GPI. Which Cells carry these receptors?

A

1) Monocytes
2) Dendritic Cells
3) Eosinophils
4) Basophils
5) Mast Cells

73
Q

TLR2:TLR6 heterodimer is associated with Lipoteichoic acid and Zymosan. Which cells are associated with these Toll-like receptors?

A

1) Monocytes
2) Dendritic Cells
3) Eosinophils
4) Basophils
5) Mast Cells

74
Q

TLR4:TLR4 homodimers ligand is lipopolysaccharide. Which cells have these receptors?

A

Macrophages
Dendritic Cells
Mast Cells
Eosinophils

75
Q

TLR7 detects single stranded viral RNAs like HIV. Which cells will have these receptors?

A

Plasmacytoid dendritic cells
NK cells,
Eosinophis
B Cells

76
Q

TLR9 detects unmethylated CpG-rich DNA. Which cells have these receptors?

A

Plasmacytoid Dendritic Cells
B Cells
Eosinophils
Basophils

77
Q

TLRs when activated will activate NF-kB and IRFs. What are the 3 signaling pathways of TLRs, and what is the role of NF-kB and IRFs?

A

NF-kB and IRFs are transcription factors

1) TRIF
2) MyD88/TRIF
3) MyD88

78
Q

Describe the TRIF, MyD88/TRIF, and MyD88 pathways.

A

TRIF: TLR3 uses only the adaptor protein TRIF to activate NF-kB and IRFs transcription proteins

MyD88/TRIF: TLR4 use both MyD88 and TRIF to activate NF- kB and IRFs

MyD88: TLRs 1, 2, 5, 6, 7, 8 and 9 use only the adaptor protein MyD88 to activate the transcription factors NF-kB and interferon- regulatory factor (IRF) transcription proteins

79
Q

In what way(s) can TLRs be detrimental to the host?

A

1) Tissue injury by inducting apoptosis in host cell

2) Lead to life-threading symptoms of septic shock

80
Q

Major CC Chemokines

A

MCP-1 (CCL2)
MIP-1B (CCL4)
MIP-3B (CCL19)
SLC (CCL21)

81
Q

Major CXC Chemokines

A

IL-8 (CXCL8)
IP-10 (CXCL10)
SDF-1aB (CXCL12)
CXCL13 (BCA-1)

82
Q

Function of MCP-1

A

Mixed leukocyte recruitment (monocytes)

83
Q

Function of MIP-1B

A

1) T cell, dendritic cell, Monocyte, and NK recruitment

2) HIV coreceptor

84
Q

MIP-3B Function

A

T cell and dendritic cell migration into parafollicular zones of lymph nodes

85
Q

Function of SLC

A

T cell and dendritic cell migration into paarafollicular zones of lymph nodes

86
Q

Function of IL-8

A

Neutrophil recruitment

87
Q

IP-10 Function

A

Effector T cell recruitment

88
Q

SDF-1aB Function

A

Homing naive B cells to LNs

89
Q

BCA-1 Function

A

1) B cell migration into follicles

2) T follicular helper cell migration into follicles

90
Q

Cytokine IL-12 produced by DCs controls what?

A

Cell-mediated immunity via T cell stimulation

91
Q

What pathways do NLRs trigger?

A

NF-kB

MAPK

92
Q

What does NLRs stand for

A

Nucleotide oligomerization domain (NOD)-like receptors

93
Q

What do NLRs control the activation of?

A

Inflammatory cascades

94
Q

What triggers an NLR response

A

1) Cytosolic PAMPs and DAMPs

95
Q

What occurs when NLRs are triggered by PAMPs and DAMPs

A

Forms a inflammasome signaling complex

96
Q

What does an NLR inflammasome do?

A

Activates Caspase-1

97
Q

What is the function of caspase-1

A

Cleaves pro-inflammatory cytokines IL-1B and IL-18 which drives inflammation

98
Q

Name things that trigger inflammasome activation

A

1) Microbial Products
2) Crystals: Uric Acid and Aluminum Hydroxide
3) Reduction in cytosolic Potassium ion concentrations
4) ATP release by mitochondria

99
Q

What is the program cell death that is caused by inflammasome activation

A

Pyroptosis

100
Q

What os Pyroptosis

A

A programmed cell death of macrophages and DCs caused by release of inflammatory mediators including IL-1B, IL-18, TNF, IL-6, and IL-8

101
Q

What are Scavenger receptors?

A

Important in tissue remodeling after collateral damage due to inflammation and infections

102
Q

List the type of scavenger receptors

A

1) Class A Type I
2) Class A Type II
3) Macrophage Receptor with Collagenous Structure

103
Q

True or False: SR KO mice don’t have an increased susceptibility to infection

A

False

104
Q

All the SR types are expressed on Macrophages. What type of antigens do they bind to?

A

They bind to bacterial constituents based on negative charges

105
Q

Name some bacterial constituents that have negative charges which allow SRs to bind to them

A

1) LPS
2) Lipoteichoic Acid
3) Nucleic Acids
4) B-glucagon
5) Proteins

106
Q

Name a way that SRs can lead to Atherosclerosis

A

1) SR-AI and SR-AII mediates the uptake of oxidized lipoproteins

107
Q

Inflammation is Innate reaction caused by:

A

1) Increased blood supply leading to redness and heat
2) Increased capillary permeability causing swelling and pain
3) Massive influx of neutrophils in the tissues
4) Arrival of monocytes/macrophages
5) Loss of function and homeostasis

108
Q

What are the 3 DAMPs that were talked about in class

A

HMGB1
Uric Acid
HSPs

109
Q

True or False: DAMPs activate NF-kB

A

True

110
Q

What is the receptor for HMGB1

A

RAGE

111
Q

What is the receptor for Uric Acid

A

NLRP3

112
Q

What is the receptor for HSP?

A

Scavenger Receptor Class A

113
Q

What are Defensins

A

Small cationic peptides with cationic and hydrophobic regions produced by epithelial cells, neutrophils, NK cells, CTLs

114
Q

How do defensins kill microbes

A

They insert into and disrupt function of microbial membranes

115
Q

True or False: Defensins synthesis is stimulated by cytokines and microbial products via PRRs

A

True

116
Q

What microbes do Defensins have direct toxicity against

A

Bacteria
Fungi
Enveloped Viruses

117
Q

Function of Defensins

A

Kill microbes and Regulate activation of immune cells involved in the inflammatory response

118
Q

IL-12 is produced by macrophages and it tells NK cells to do what?

A

Secrete IFN-y

119
Q

What is the function of IFN-y

A

Activates macrophages to kill phagocytized microbes

120
Q

How do NK cells kill Target Cells

A

1) NK cell releases performing which polymerize and form a hole in the enemy cell membrane
2) Granzymes from NK cell enter performing hole and degrade enemy cell enzymes
3) Enemy Cell dies by apoptosis
4) Macrophage engulfs and digests dying cell

121
Q

What type of cells do NK cells kill?

A

Stressed Cells

Infected Cells

122
Q

What two important receptors do NK cells have?

A

1) Activating Receptors (KARs)

2) Inhibitory Receptors (KIRs)

123
Q

Purpose of KARs

A

recognize stress-associated molecules on the surface of abnormal host cells

124
Q

Purpose of KIRs

A

Recognize class I MHC and activate protein tyrosine phospjatases (PTP) inhibit and activation signal

125
Q

What happens when there is insufficient KIR-MHC I binding?

A

NK cell will proceed to kill the target host cell

126
Q

Sufficient binding by KIRs will do what?

A

Override the KAR kill signal sparing the life of the host cell

127
Q

Systemic Pathological Effects of TNF

A

1) Low cardiac output
2) Increased permeability of blood vessels
3) Thrombus of blood vessels
4) Insulin resistance in skeletal muscle

128
Q

Systemic Protective effects of TNF, IL-1, and IL-6

A

1) Acts on the brain to cause fever
2) IL-1 and IL-6 act on liver to cause production of acute phase proteins
3) Acts on bone marrow to cause leukocyte production

129
Q

How can CRP and SAP activate complement

A

They can bind to C1q and initiate the classical pathway

130
Q

CRP and SAP recognize ….. and ……., respectively, which are found on bacteria and apoptotic cells

A

Phosphorylcholine

Phosphatidylethanolamine

131
Q

CXCL8

A

IL8

132
Q

What are L-selections?

A

L-selections (CD62L) expressed on lymphocytes

They will bind to L-selection ligand that is expressed on the surface of HEVs with high affinity for the receptor

133
Q

What is another name for L-selectin ligands

A

Peripheral Node Addressins (PNAd)

134
Q

What is most important for homing of NIAIVE t and b lymphocytes into lymphonodes?

A

The interactions between L-selectin and L-selectin Ligand

135
Q

Name the Integrins

A

LFA-1
Mac-1
VLA-4
a4-b7 integrin

136
Q

List the integrins and their ligands

A

LFA-1 - ICAM- 1 and 2
Mac-1 - ICAM - 1 and 2
VLA-4 - VCAM -1
a4b7 integrin VCAM-1 and MadCAM-1

137
Q

In what conformation are integrins expressing their highest affinity>

A

In their extended conformation. When they are in bent conformation, they are in their lowest affinity

138
Q

CCL19

A

MIP3B

139
Q

CCL21

A

SLC

140
Q

CCL4

A

MIP1B

141
Q

CCL2

A

MCP1

142
Q

CXCL10

A

IP-10

143
Q

CXCL13

A

BCA-1

144
Q

CXCL12

A

SDF-1ab

145
Q

What are other names for CXCL10 and CCL4, and what are they primarily used for?

A

Chemotaxis to peripheral tissues and activation of integrins

146
Q

What Chemokines are used for naive T cell homing in the lymph nodes?

A

CCL19 or CCL21

147
Q

Where do immature naive B cells mature?

A

White Pulp

148
Q

Where is CXCL12 expressed and what does it do?

A

CXCL12 is also known as SDF-1ab and it is expressed on HEVs and their Chemokines receptors. This is going to aid in intergrin activation

149
Q

What Chemokines is drives B cells into the B cell zone of the LN?

A

CXCL13 which is also know as BCA-1

150
Q

Name all the ligands that can be detected by TLRs

A 
Lipopeptides 
GPI
Lipoteichoic Acid
Zymosan
Lipoplysaccharide
Flagellin 
Single-stranded viral RNAs
Double-stranded viral RNA
Unmethylated CPG-rich DNA
151
Q

List all of the complement regulators

A

DAF
CR1
Factor I

152
Q

Function of DAF in terms of complement regulation

A

Blocks C2:C4b interaction and C3b:Bb interaction

Enhance dissociation of C4bC2a and C3bBb

153
Q

Function of CR1

A

1) Receptor for C3b and aids in activation of phagocytosis
2) Enhances dissociation of C4bC2a interaction
3) Prevents assembly of the C3 and C5 convertaSE WITH AID FROM FACTOR I

154
Q

Factor I is also known as what?

A

C3b/C4b inactivator

155
Q

Functions of Factor I

A

1) Prevents assembly of C3 and C5 convertaSE via cleavage of C4b and C3b; will use CR1 as a cofactors

Immunology Test 1 (1 decks)

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