Immunology Flashcards

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1
Q

The function of the immune system is to…..

A

Prevent and control infections, eliminate pathogens and their harmful products.

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2
Q

The immune system is characterized by layering and redundancy. WTF does that mean?

A

Layering- Multiple layers of protection.

Redundancy- A single pathogen can be fought by the immune system in multiple ways.

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3
Q

What are the two major types of immunity?

A

Innate, Adaptive/acquired

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4
Q

Pathogen motif receptors and Antigen-specific receptors are used to tell the difference between….

A

Self and Non Self

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5
Q

Blood is an important component of the immune system, it contains….

A

Leukocytes, Lymphocytes, Clotting Factors, Complement, Antibodies

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6
Q

The immune response consists of two parts, ____ and recruitment of effector mechanisms.

A

Recognition of pathogens

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7
Q

What do Lymph Nodes do?

A

Filter interstitial fluids, removes antigens and makes them available to B/T cells, place for B cells to make antibodies.

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8
Q

Which immune system is present at birth, and is always present at basal levels?

A

Innate immunity

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9
Q

T or F. The innate immunity provides immunological memory.

A

False. Adaptive/acquired immunity

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10
Q

T Lymphocytes have _____ that recognize the pathogen participate in the adaptive response.

A

Receptors

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11
Q

What are the two categories of adaptive immunity?

A

Humoral, Cell Mediated

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12
Q

What cellular/noncellular components make up innate immunity?

A

Leukocyte, Biochemical constituents (enzymes), anatomical/physical barriers, proteins (complement, cytokines, chemokines), inflammation

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13
Q

What are the 3 properties that make Adaptive Immunity so effective and protective?

A

Diversity, Specificity, and Memory

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14
Q

_____ respond to a single foreign antigen and become activated only when that antigen is encountered.

A

Lymphocytes

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15
Q

Name the 3 states of a mature Lymphocyte.

A

Naive, Effector, Memory

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16
Q

Name 3 different Leukocytes/Granulocytes.

A

Basophils, Eosinophils, Mast Cells

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17
Q

Antigen Presenting Cells engulf pathogens and present them to T Cells. Name 3 types of APCs.

A

Dendritic cells, macrophages, B cells

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18
Q

_____are produced by activated B-Cells.

A

Antibodies

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19
Q

_____are mainly produced by activated immune cells like T-cells, Macrophages, and NK cells.

A

Cytokines

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20
Q

This subset of the adaptive immunity protects against EXTRAcellular pathogens.

A

Humoral Immunity

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21
Q

T or F? CD4 TH1 is found in the Humoral Immunity.

A

False. CD4 TH2

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22
Q

This subset of the adaptive immunity protects against INTRAcellular pathogens.

A

Cell Mediated Immunity

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23
Q

Phagocytes process and present enulfed antigens to T Helper cells to activate what?

A

Adaptive Immunity

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24
Q

The production and secretion of what results in the upregulation of MHC class I molecules for more productive antigen presentation to cytotoxic T cells?

A

Interferon (IFN)

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25
Q

_____on the surface of an antigen can enhance B cell activities.

A

Complement Proteins

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26
Q

Cytokines upregulate ______ molecules on phagocytes for better antigen presentation to T Helper cells.

A

MHC class II

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27
Q

What recognizes LPS and sends a signal to activate NF-kappaB which leads to production of cytokines and the upregulation of molecules important for B/T cell activation?

A

TLR 4

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28
Q

Name 3 ways the adaptive immunity activates/regulates the innate immunity?

A

T cells produce cytokines that enhance phagocytosis and oxidative burst.

Antibodies bound to the surface of an antigen increase their uptake by phagocytes (opsonization)

Cytokines produced by activated CD4 T cells (T 1 Helper cells) activate macrophages and upregulate expression of Fc receptors on macrophages, NK cells, and neutrophils.

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29
Q

The ____branch of the adaptive immunity has both T helper 1 and T helper 2 cells.

A

Humoral

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30
Q

What is the single effector function of B cells?

A

To produce antibodies

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31
Q

What is a membrane form of an antibody that plays an important role in B cell activation?

A

B Cell Receptor (BCR)

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32
Q

What is the role of soluble (secreted antibodies)?

A

Recognize and bind extracellular pathogens and their products and deliver them to phagocytes for removal

(edited by KH)

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33
Q

What allows antibodies to share common effector functions?

A

Conserved sequences.

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34
Q

T or F? Antibodies can kill and remove pathogens by themselves.

A

False.

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35
Q

The specificity of an antibody is attributed to to the _____ region.

A

Variable.

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36
Q

The biological activity of an antibody is determined by the _____ region.

A

Constant.

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37
Q

Do constant regions of antibodies differ between different isotypes?

A

Yes.

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38
Q

How many light and heavy chains does an antibody molecule have?

A

2 Heavy, 2 Light.

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39
Q

The two L chains do NOT interact with each other.

A

……

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40
Q

What type of bond connects each L chain to an H chain?

A

Interchain disulfide bonds.

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41
Q

What type of bond connects the two H chains to one another?

A

Interchain disulfide bonds.

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42
Q

How heavy are heavy chains?

A

50,000 Da

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43
Q

How heavy are light chains?

A

25,000 Da

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44
Q

The variable region of the L and H chains determine specificity. Where is the variable region?

A

The N-Terminal.

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45
Q

Why do different antibody isotypes have different functions?

A

The constant regions.

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46
Q

The constant region of the heavy chain is subdivided into __domains.

A

Three

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47
Q

The constant region of the light chain is subdivided into __ domains.

A

One

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48
Q

Which Immunoglobulins have 4 CH domains?

A

IgM, IgE

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49
Q

The antibody molecule can be divided into functional regions, they are……

A

Fab- Fraction antigen binding

Fc- Fraction crystallizable

Hinge- Present in IgG, IgA, and IgD (all have 3 CH domains)

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50
Q

What enzyme is capable of breaking an antibody into 2 Fab and 1 Fc?

A

Papain

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51
Q

This region of an antibody retains the ability to bind antigen, consists of the VH, VL, CL, and CH1 domains. Each full antibody also contains TWO of these fragments.

A

Fab

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52
Q

What two distinct functions are served by the Fc region?

A

Delivers the antibody to specific anatomical sites (she spells it sights in her notes….?)

Assists in Opsonization by binding to Fc receptors on immune cells that phagocytose the attached antigen.

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53
Q

This portion of the antibody molecule contains CH2, CH3, and CH4 (if it exists), and most of the hinge.

A

Fc

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54
Q

How many fragments of Fc per antibody?

A

One

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55
Q

If Pepsin is used to generate an F(ab)2, which portion was NOT generated?

A

Fc. It is cleaved BELOW the hinge.

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56
Q

What AA residues primarily make up the hinge region?

A

Pro, Ser, Thr

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57
Q

What allows the 2 Fab arms to open/close to accommodate binding to 2 epitopes?

A

The Hinge region

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58
Q

The hinge region is found between what two domains?

A

CH1 and CH2

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59
Q

T or F? IgG, IgA, and IgD all have 3 CH regions, which means they DO NOT have a hinge region.

A

False, they do! Seriously. They do.

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60
Q

What two fragments retain the ability to bind antigen?

A

Fab and F(ab)2

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61
Q

What is the small glycoprotein associated with POLYMERIC IgA and IgM (Not hexameric IgM)?

A

J chain

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62
Q

How many J chains per antibody?

A

One

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63
Q

What is the function of the J chain?

A

Polymerization and interaction with the poly-Ig receptor (transports antibodies from the basal side of the epithelium onto the luminal side of the mucosal surface)

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64
Q

What type of bonds give antibody molecules their globular shape and separate the domains of each chain?

A

Intra chain S-S Bonds

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65
Q

Which portions of the L chain interact with what portions of the H chain in the Fab portion?

A

VL with VH

CL with CH1.

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66
Q

Within the Fc portion, the CH3 domains interact, but the two _____ domains do not.

A

CH2

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67
Q

The V region is subdivided into what two regions?

A

Hypervariable and framework regions.

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68
Q

What region of the Variable region actually makes contact with the epitope?

A

Hypervariable

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69
Q

The hypervariable region is present in both the VL and VH regions. True or false: There are 3 different stretches of 8-11 AAs in both regions.

A

True

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70
Q

Hypervariable regions are also known as……

A

Complementarity-Determining Regions.

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71
Q

How many CDRs per monomeric antibody molecule?

A

12 (3 from each L chain and 3 from each H chain)

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72
Q

The remaining 80ish AAs of the V region between CDRs are called…..

A

Framework Regions

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73
Q

How many Framework regions in each V region?

A

Four

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74
Q

What are the two types of light chains?

A

Kappa and Lamdba

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75
Q

T or F? Both L chains in a given antibody molecule are NOT the same.

A

False. They are identical (both Kappa or Lambda)

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76
Q

T or F? There is no known effector function associated with the L chain.

A

True.

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77
Q

What chain determines the class/isotype and the effector function of the antibody?

A

H-Chain

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78
Q

What are the 5 major H chain isotypes?

A

IgA, IgD, IgE, IgG, IgM

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79
Q

IgG is subdivided into how many classes in humans?

A

Four. IgG1, IgG2….

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80
Q

IgA is subdivided into how many classes in humans?

A

Two. IgA1, IgA2

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81
Q

T or F. Since Isotype is determined by the C region, it has nothing to do with antigen specificity.

A

True. Specificity is controlled by the V region.

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82
Q

What is the first isotype secreted when B cells are activated by T cells?

A

IgM

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83
Q

IgM is made almost exclusively as a _____, but has been found as a hexamer.

A

Pentamer.

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84
Q

What is the most efficient isotype for activating the classical complement pathway?

A

IgM

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85
Q

What is the only isotype made by a fetus?

A

IgM

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86
Q

What is the half life of IgM?

A

5 days

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87
Q

If you have an IgA deficiency, how does that affect IgM secretion?

A

IgM secretion increases.

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88
Q

What is the major source of IgM in saliva?

A

Gengival cervicular fluid

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89
Q

What is the half life of IgG?

A

23 days. Except for IgG3, which is 7 days.

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90
Q

What isotype is the most abundant in tissues and serum?

A

IgG

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91
Q

What is the only isotype that crosses the placenta?

A

IgG (IgG1>IgG3>IgG2>IgG4)

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92
Q

Which isotype is bound Fc receptors and can participate in ADCC?

A

IgG

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93
Q

When does IgG production start in infants?

A

4-6 months

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94
Q

The small size of IgG allows it to do what?

A

Cross the vasculature and endothelium.

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95
Q

Which subtype of IgG is found in about 50% of the Caucasian population?

A

IgG2

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96
Q

How many subclasses of IgA are in humans?

A

Two

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97
Q

WHat is the half life of IgA?

A

Five days

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98
Q

What is special about dimeric IgA + Lysozyme?

A

It can kill a pathogen (Protective for breast fed infants).

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99
Q

_____is usually directed against protein epitopes.

A

IgA1

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100
Q

_____is usually directed against polysaccharide epitopes.

A

IgA2

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101
Q

The most abundant of all the antibodies.

A

IgA

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102
Q

What is the most predominant isotype found in secretions and mucosal surfaces?

A

IgA (specifically Dimeric SIgA)

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103
Q

Where is most monomeric IgA found?

A

The serum

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104
Q

IgA is second to ____ in regards to being found in serum.

A

IgG

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105
Q

SIgA is secreted by salivary glands into the…..

A

Oral cavity

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106
Q

Most IgE is bound to ____receptors on the surface of mast cells, basophils, and eosinophils.

A

Fc-epsilon

107
Q

What is the half life of IgE?

A

Two days

108
Q

This isotype mediates immediate hypersensitivity reactions.

A

IgE

109
Q

Most IgE secreting plasma cells are thought to be located primarily in the ______

A

Pharyngeal tonsils

110
Q

IgE binds to _____, casusing degranulation of attached granulocytes.

A

Parasites

111
Q

Which isotype is found primarily on the surface of naive, mature B cells after they leave the bone marrow?

A

IgD

112
Q

What role does IgD hold as a BCR?

A

B cell activation

113
Q

What is the least common Ig made?

A

IgD

114
Q

If IgD is missing from the B cell surface, what can happen?

A

Self reactive B cells can enter lymphoid organs and proliferate.

115
Q

What isotypes contain a J chain?

A

IgA + IgM

116
Q

What isotype contains an S component?

A

IgA

117
Q

What study partners do you stay up for until 2am working on cards so you won’t let them down?

A

Karin Hwang

Sarah Stamper

118
Q

What is hematopoiesis?

A

the production of immune cells

119
Q

What cells develop into cells of all different lineage and function?

A

Pluripotent stem cells

120
Q

What can hematopoetic stem cells develop into?

A
Self- renewing stem cell
Myeloid cell (and later into RBC, erythroid cells, monocytes/macrophages and granulocytes)
Lymphoid cell (T cell, B cell, NK cell)
121
Q

Where do hematopoiesis occur in children and adults?

A

Bone marrow and Thymus

122
Q

How long do monocytes circulate in the blood?

A

1-3 days

123
Q

How do macrophages relate to monocytes?

A

Macrophages are monocytes that have exited the blood and become fixed in tissues

124
Q

What is another name for macrophages that have exited the blood and become fixed in tissues?

A

Tissue Fixed Macrophage

125
Q

What are common surface receptors for macrophages?

A

CR3 (complement receptor 3) and Fc (the Fc portion of IgG and IgE antibodies)

126
Q

What is the role of the CR3 surface receptor on macrophages?

A

allows for complement protein C3B to bind (aids in opsonization)

127
Q

What is the role of Fc surface receptor on macrophages?

A

Aids in opsonization or ADCC (Antibody-dependent cell-mediated cytotoxicity)

128
Q

How can macrophages be activated from their resting state?

A

1) Interferon-gamma
2) Pathogen-Associated Molecular Patterns (PAMPs)
3) Opsonization

129
Q

Opsonization is ______________ of antibody-coated or complement coated antigen that occurs via Fc or CR3 receptors

A

enhanced phagocytosis

130
Q

What are the main functions of macrophages?

A
  • Phagocytosis
  • Antigen Processing & Presentation
  • Production of soluble mediators
  • Antibody-dependent Cell-mediated Cytotoxicity (ADCC)
131
Q

What are the 3 states for macrophages?

A

1) Resting
2) Activated
3) Hyperactivated

132
Q

Resting macrophages are also known as ______________, because they take up debris and dead cells.

A

“garbage collectors”

133
Q

How is phagocytosis in activated macrophages different than resting macrophages?

A

Activated macrophages actively take up foreign invaders by recognition of a PAMP or opsonization.

134
Q

How do hyperactivated macrophages kill pathogens?

A

Hyperactivated macrophages secrete cytokines and complement proteins and kill pathogens via OXIDATIVE BURST.

135
Q

What is oxidative burst?

A

The release of toxic oxygen and nitrogen radicals (NO, NO2, HNO2, HCLO-, H2O2, O2-)

136
Q

How does antigen processing and presentation work with macrophages?

A

Macrophages break down (“processes”) antigens into small peptide fragments and “presents” the antigen on its surface to T cells via MHC class I or II molecules.

137
Q

Name an example of a PAMP (pattern associated molecular pattern).

A

PRR (pattern recognition receptor)

138
Q

When the first phagocytic cell (like a macrophage) senses an invading microbe, what does it do?

A

It phagocytoses it and begins secreting cytokines

139
Q

What cytokines does the first phagocytotic cell that senses an invading microbe release?

A

IL-1, IL-6, TNF-alpha

IL = Interleukin

140
Q

What soluble mediators do macrophages release?

A

cytokines and complement proteins

141
Q

For macrophages, what is Antibody-dependent cell-mediated cytotoxicity?

A

When the macrophage detects a target coated with a ton of a specific antibody, it releases radicals and enzymes at the surface to kill the target cell WITHOUT phagocytosis.

142
Q

ADCC via macrophages occurs when the target is coated with what specific antibodies?

A

IgG

143
Q

Which cell in the immune system is the best for phagocytosis?

A

Neutrophils

144
Q

What are neutrophils?

A

Short lived dedicated killers that circulate in the blood until recruited.

145
Q

What is the most predominant granulocyte, making up >90% of circulating granulocytes and 50-70% of all circulating WBC?

A

neutrophils

146
Q

What is another name for neutrophil?

A

Polymorphonuclear cells (PMNs) because of their multilobed nucleus

147
Q

What is immunopathology?

A

The release of enzymes that result in collateral damage to innocent cells during an infection

148
Q

How long do Neutrophils live?

A

less than or equal to 2 days

149
Q

What are the main functions of neutrophils?

A

Phagocytosis and cytokin production.

150
Q

What do neutrophils release during phagocytosis?

A

Lytic enzymes and Defensins

151
Q

What are defensins?

A

Small peptides that poke holes in membranes to kill phagocytosed pathogens

152
Q

True or false: Neutrophils also have oxidative burst, like macrophages.

A

True

153
Q

What pro inflammatory cytokines do Neutrophils produce?

A

IL-1, IL-6, IL-8, TNF-alpha

154
Q

Which granulocytes have high affinity surface receptors for IgE antibodies?

A

Eosinophils, Basophils and Mast cells

155
Q

Which granulocyte has low affinity surface receptors for IgG antibodies?

A

Eosinophils

156
Q

What is a key role of eosinophils?

A

Fighting parasitic infections

157
Q

True or False: Eosinophils are not phagocytic.

A

False; eosinophils are phagocytic.

158
Q

Which granulocytes have a role in allergic reactions?

A

Eosinophils (major role), Mast cells (major role), and Basophils (minor role)

159
Q

Which granulocyte has an important role in the pathogenesis of asthma and other chronic inflammatory diseases?

A

Eosinophils

160
Q

What is degranulation?

A

The release of contents from granules

161
Q

Which granules do basophils and mast cells release during degranulation?

A

histamine and vasodilators

162
Q

Where are mast cells normally found?

A

Along connective tissue and skin

163
Q

What is the main function of platelets?

A

Involved in blood clotting & inflammation

164
Q

What amount of platelets are in circulation vs. in the spleen?

A

2/3 in circulation; 1/3 in spleen

165
Q

Platelets have surface receptors for what?

A

1) Fibrinogen (clotting)
2) Complement protein C3b (inflammation)
3) Cytokines (CXCR4)

166
Q

How do you ID dendritic cells (DCs)?

A

They have cytoplasmic extensions called dendrites.

167
Q

Where are dendritic cells (DCs) found?

A

Mostly in the skin and 0.1% in the blood (i.e. rarely found in circulation)

168
Q

What is main role of dendritic cells (DCs)?

A

Migrate to the hearest lymphoid organ to present to T cells

169
Q

Name the four major functions of DCs.

A

1) Phagocytosis
2) Antigen presentation
3) Negative selection
4) Cytokine production

170
Q

True or False: Immature and mature DCs are phagocytic.

A

False! Only immature DCs are phagocytic. Mature DCs are NOT phagocytic.

171
Q

Which cell is the most are the most effective antigen presenting cells (APCs)?

A

dendritic cells (DCs)

172
Q

Immature DC phagocytoses antigen and then ______ to a secondary lymphoid organ where they mature to interdigitating cells to ___________________ to T cells.

A

migrates; present processed antigens

173
Q

DCs cell present antigens via _____________ to CD4+ cells.

A

MHC class II molecules

174
Q

DCs cell present antigens via _____________ or _______ to CD8+ cells.

A

MHC class I molecules or CD1

175
Q

In the thymus, DCs present self-antigens to developing T cells to determine if the developing cell is self-reactive and needs to be destroyed. What is this process called?

A

Negative selection

176
Q

What is a thymocyte?

A

a developing T cell

177
Q

What cytokines do DCs cells produce?

A

IL-1beta, TNF-alpha, IL-12

IL = interleukin

178
Q

T or F: Follicular Dendritic Cells have nothing to do with Dendritic Cells.

A

True.

179
Q

T or F: Follicular dendritic cells (FDCs) are phagocytic.

A

False. Follicular cells are NOT phagocytic. Antigen binds to FDC surface, but is not internalized.

180
Q

Where are Follicular Dendritic cells (FDCs) found?

A

In germinal centers & follicles of lymphoid tissues

181
Q

Follicular dendritic cells (FDCs) are involved in Antigen presentation to ________.

A

B cells. Note: They present whole, unprocessed antigen to B-cells to keep them activated during affinity maturation.

182
Q

Follicular dendritic cells (FDCs) are related to the humoral or adaptive immune system?

A

Adaptive Immune System, since the B cells improve their antibodies.

183
Q

FDCs do not express MHC molecules. What does this mean?

A

They cannot present processed antigens to T cells!

184
Q

FDCs have extensive surface processes that bind ___________ via the Fc portion of the antibodies.

A

antigen-antibody complexes

185
Q

The dendrites of FDC cells are covered with Fc receptors that allows them to do what?

A

Present whole, unprocessed antigens to B-cells in lymphoid germinal centers.

186
Q

How does FDC’s present antigens to B cells affect B cells?

A

Results in affinity maturation of B cells and maintenance of immunologic memory of B cells.

187
Q

All T cells have a surface receptor called …?

A

T cell receptor (TCR)

188
Q

What is the role of TCR?

A

TCRs recognize a specific particular antigen.

189
Q

T cells are categorized into sub populations based on what?

A

Function and surface proteins

190
Q

What are the two subcategories for T cells?

A

CD4+ and CD8+

191
Q

What is the effector function for CD4+ T cells?

A

the production of cytokines

192
Q

What is the effector function for CD8+ T cells?

A

kill infected host cells or tumor cells

193
Q

True or False: CD4 and CD8 are antigen co-receptors.

A

True

194
Q

True or False: CD4 and CD8 are expressed in a mutually exclusive fashion.

A

True

195
Q

CD4 recognizes which MHC Class molecules?

A

MHC Class II

196
Q

CD8 recognizes which MHC Class molecules?

A

MHC Class I

197
Q

CD4 T-Helper cells can be subdivided based on _______________________.

A

cytokine production

198
Q

What molecules play an important role in the development of T-helper 0 cells into TH1 and TH2 cells?

A

Cytokines

199
Q

What cells produced by TH1 cells inhibit TH2 differentiation?

A

Interferon-gamma (INF-gamma)

200
Q

Which cytokines inhibit TH1 differentiation?

A

IL-4 and IL-10 produced by TH2 cells

201
Q

Which cytokines favor TH1 differentiation?

A

IL-12 (produced by DCs, Macrophages, and neutrophils)

202
Q

What are the main functions of T-helper 1 cells?

A

Produce cytokines
Stimulate CD8+ T Cells (cell-mediated response)
Stimulate isotype switching in B cells

203
Q

Which T cells stimulate CD8+ T cells?

A

CD4+ T-helper 1 cells

204
Q

Which T cells stimulate B cells to produce antibodies?

A

CD4+ T-helper 2 cells

205
Q

What are the main functions of T-helper 2 cells?

A

Produce cytokines
Stimulate B cells to produce antibodies (humoral response)
Stimulate isotype switching in B cells

206
Q

T-helper 1 cells stimulate isotype switching in B cells to produce what?

A

IgG2, IgG3, and IgA

207
Q

T-helper 2 cells stimulate isotype switching in B cells to produce what?

A

IgG1, IgE, and IgA

208
Q

TH1 and TH2 phenotype can affect clinical presentation and severity the disease. Dominance of which one results in horrible allergies?

A

T-helper 2 cells (TH2)

209
Q

If leprosy is an intracellular pathogen, which type of CD4+ cells do you need to battle it?

A

T-helper 1 cells (TH1). They work to stimulate CD8+ T cells, which is a cell mediated response (which affect intracellular).

210
Q

T or F: Most adaptive immune responses involve both TH1 and TH2 cells, with a bias toward one or the other.

A

True

211
Q

What are other names of CD8+ T cells?

A

Cytotoxic T cells, Tc, or CTL

212
Q

What is the role of CD8+ T cells or Cytotoxic T cells?

A

Kill target cells through the release of cytotoxic enzymes and receptor mediated apoptosis.

213
Q

Which T cells result in the direct killing of an infected target cell?

A

CD8+ T-cell

214
Q

B lymphocytes have a surface receptor for antigen called what?

A

B cell receptor (BCR)

215
Q

Naive B cells have what antibodies on their surface.

A

IgM and IgD

216
Q

Activated B cells have only 1 type of BCR on their surface. Which antibodies/BCR can they have?

A

IgM, IgG, IgE, or IgA (essentially all of them except for IgM)

217
Q

B lymphocytes can express what type of MHC molecules?

A

I and II

218
Q

What surface receptors are on B lymphocytes?

A

Fc-gamma (for IgG) and epsilon (for IgE)
CD40
CD80/CD86

219
Q

CD40 on B-lymphocytes interact with what on T cells?

A

CD40L

220
Q

When CD40 on B-cells interact with CD40L on T cells, what happens?

A

This second activating signal for B cells signals the B cell to undergo isotype switching.

221
Q

When CD80.CD86 (B7) on B-cells interact with CD28L on T cells, what happens?

A

it provides the second activation signal for the T cell and initiates isotype switching for T cells.

222
Q

Terminally differentiated B cells that become antibody factories are?

A

Plasma cells.

223
Q

T or F? Plasma cells produce antibodies with specificity for multiple antigens.

A

False. Single Antigen

224
Q

____ develop from Naive B Cells activated by antigen. They return to a resting state waiting to be activated again.

A

Memory B Cells

225
Q

B cells take up antigen through the membrane bound antibody (BCR) or through what?

A

PRRs on their surface (TLR)

226
Q

____cells have no TCR or BCR and are part of the innate and adaptive immune systems.

A

NK (Natural Killer) cells.

227
Q

NK cells kill via ADCC when ____receptors on cell surface bind IgG coated antigen.

A

Fcy

228
Q

NK cells recognize ____on the surface of tumor cells.

A

MICA

229
Q

NK cells stimulate cytotoxic activity of ___cells and activate macrophages.

A

Tc

230
Q

Name the primary lymphoid organs.

A

Bone Marrow, Thymus.

231
Q

Cells that eventually become B cells remain in the _____

A

Bone Marrow

232
Q

Cells that become ____ cells leave the bone marrow and enter the thymus.

A

T Cells

233
Q

The process in which self reactive T cells are eliminated, while those that do not recognize self antigens enter the bloodstream is called?

A

Thymic Selection

234
Q

What happens (in general) in the secondary lymphoid organs?

A

Mature B/T cells interact with antigen, allowing them to undergo further differentiation and proliferation.

235
Q

Red pulp acts as a filter to remove…..

A

Pathogens and damaged RBCs

236
Q

25% of the body’s mature lymphocytes are contained in the….

A

White pulp of the Spleen

237
Q

After pathogens exit the blood of the red pulp, they encounter immune cells in the……

A

White Pulp

238
Q

Where are blood borne antigens processed and presented?

A

White Pulp

239
Q

Where are antigens from the tissues processed and presented?

A

Lymph Nodes

240
Q

How do pathogens arrive in MALT?

A

Direct delivery across the mucosa by specialized mucosal epithelial cells.

241
Q

MALT consists of…..

A

D-MALT, O-MALT, GALT, BALT

242
Q

For antibodies to be made, ____and ____ cells specific for the antigen must interact.

A

T and B

243
Q

T or F. The majority of lymphocytes are in the blood.

A

False. Lymphoid tissues.

244
Q

Naive T cells have ______ surface receptors that allow them to enter lymph nodes.

A

L selectin

245
Q

Where do Naive T cells migrate to? (Hint, this is where antigens are on display by professional APCs)

A

T Cell Zone

246
Q

Why do Effector T cells not reenter other lymph nodes to search for antigen?

A

They lose their L-Selectin receptors

247
Q

Where do Effector T Cells preferentially migrate to?

A

Tissues

248
Q

Some mature cells reenter lymph nodes where they can mount a secondary immune response. These are called…..

A

Memory T cells

249
Q

_____and______ are next to one another and adjacent to sites where antigens enter the lymphoid tissue.

A

B cell zones and T cell zones.

250
Q

What is Psoriasin?

A

Small fatty acid with antibacterial and chemotactic properties.

251
Q

Sebum is sometimes used by bacteria as a nutrient. It also lowers skin pH to about….

A

4

252
Q

Keratinocytes stimulate inflammation and attract monocytes to the injury through the production of what?

A

Cytokines and Chemokines

253
Q

Langerhans cells are located…..

A

Between and among epithelial cells.

254
Q

_____consists of 90% of our surfaces exposed to antigens, and are 80% as effective as skin despite being only one cell layer thick.

A

Mucosal Surfaces

255
Q

Mucus generally contains…..

A

Glycoproteins, proteoglycans, and enzymes.

256
Q

______move mucus trapped particles to the pharynx, where they are swallowed and expelled.

A

Cilia

257
Q

Tears contain _____.

A

Lysozyme

258
Q

What is the immunological function of fevers?

A

Retard and prevent growth of pathogens.

259
Q

Lysozyme and Lactoperoxidase are found in…..

A

Tears, Mucus, and Saliva

260
Q

______cleave and destroy extracellular proteins on pathogen surface.

A

Proteases

261
Q

How do Antimicrobial peptides destroy membrane integrity?

A

Insert into membrane.

262
Q

Antimicrobial Peptides (Defensins) are most effective against what kinds of bacteria and viruses?

A

Gram negative bacteria and enveloped viruses.

263
Q

Where are Antimicrobial peptides (Defensins) found?

A

Mucosal secretions and cytoplasmic granules of phagocytes.