Immunology Exam 2 (Complement, Ags/Abs, Cytokines, MHC) Flashcards

1
Q

Five major classes of antibodies in order of abundance

A

IgG, IgA, IgM, IgD, IgE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the key element of the humoral immune response?

A

Antibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Isotypes

A

Unique amino acid sequence common to all antibodies of a given class, identical in all individuals of a species and differ between species (IgG is an isotype)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Allotypes

A

Minor variations of amino acid sequences that are present in some individuals of the same species, but not all
(Such as IgG1, IgA2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Idiotypes

A

Variations in variable regions that give individual antibody molecules specificity (Binds to the antigen, different)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where do antibodies appear on serum electrophoresis?

A

Gamma band at pH 8.6

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are antibodies held together by?

A

Noncovalent forces and disulfide interchain bridges

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Basic structure of an antibody

A

2 heavy chains
2 light chains
Fab region at the Y
Fc region at straight part of Y

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Purpose of the Fc region

A

Has no antigen-binding ability
Can bind complement and important for opsonization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

White cells that have Fc regions would be which cells?

A

Neutrophils and monocytes (opsonization –> phagocytosis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where are light chains located on an antibody?

A

Outside portions of the “Y” structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Purpose of the Fab region

A

Binds antigens (2 binding sites per Fab region)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which part of an antibody is obtained by papain digestion?

A

2 Fab fragments and one Fc fragment, horizontal cut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which part of an antibody is obtained by pepsin digestion?

A

F(ab’)2, vertical cut, Fc portion in nonfunctional pieces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are Bence Jones Proteins?

A

Light chains, kappa and lambda
Can be secreted by malignant plasma cells and associated with multiple myeloma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What disease states are associated with Bence Jones Proteins?

A

Multiple myeloma
Heat shock (goes back to normal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is unique to each class and gives each immunoglobulin type its name?

A

Heavy chains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What heavy chain is on an IgG?

A

gamma chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What heavy chain is on IgA?

A

alpha chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What heavy chain is on IgD?

A

Delta chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What heavy chain is on IgE?

A

Epsilon chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What heavy chain is on IgM?

A

Mu chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the hinge region?

A

The segment of heavy chain located between CH1 and CH2 regions - disulfide bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What has a high content of proline, allowing flexibility, and hydrophobic residues?

A

Hinge region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What allows two antigen-binding sites to operate independently and assists initiation of complement cascade?

A

Hinge region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What has the longest half life of any Ig?

A

IgG, 23 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What IgG molecules are best at activating complement?

A

IgG3 is the best, then IgG1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Most predominant allotype of IgG

A

IgG1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Why is IgG3 the best at activating complement?

A

Super long hinge region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What IgG allotypes are poor mediators of complement activation and why?

A

IgG2 and IgG4 ; they have shorter hinge segments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Major functions of IgG

A

Provide immunity for newborn (can cross placenta)
Activates complement
Opsonization
Neutralizing toxins and viruses
Agglutination/Precipitation rxn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

T/F: All allotypes of IgG can cross the placenta.

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

T/F: IgG is better at agglutination reactions than at precipitation reactions.

A

False. IgG is better at precipitation reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is the half life of IgM?

A

6 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Where is IgM found as a monomer? Where is IgM found as a pentamer?

A

Monomer: on surface of B cells
Pentamer: secretions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Which Ig molecule is known as the macroglobulin?

A

IgM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

How many binding sites does IgM have?

A

5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Which antibody has a high valency, high affinity, low avidity?

A

IgM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

T/F: IgM has memory cells

A

False

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Functions of IgM

A

Complement fixation
Agglutination
Neutralization
Primary Response Antibody
Opsonization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is known as the primary response antibody?

A

IgM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Where is IgA1 found?

A

Blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Where is IgA2 found?

A

Mucosal surfaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Secretory IgA functions

A
  • Patrols mucosal surfaces and acts as a first line of defence
  • Passively transfers immunity to newborn during breastfeeding
  • Indirectly activate complement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What cells possess specific receptors for serum and secretory IgA?

A

Neutrophils, monocytes, and macrophages

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What Ig is on the surface of B cells only?

A

IgD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What Ig attaches to basophils and eosinophils and tissue mast cells?

A

IgE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What Ig has to do with allergic reactions?

A

IgE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Somatic hypermutation

A

Genetic mutations during the course of the immune response that result in stronger binding of antigen (affinity maturation)

50
Q

Factors influencing the immune response

A
  • Age
  • Health
  • Route of inoculation
  • Dose
  • Genetic capacity
51
Q

Immunogen

A

A substance capable of stimulating an adaptive immune response

52
Q

Antigen

A

A substance specifically recognized by the immune system and is the target of the immune response

53
Q

Not all ________ are ________, but all ________ are _________.

A

not all antigens are immunogens, but all immunogens are antigens

54
Q

_____ are the most effective immunogens, follow by _____.

A

proteins, polysaccharides

55
Q

Haptens

A

substances that are non-immunogenic by themselves

56
Q

Adjuvants

A

Enhances immune response, accelerates/increases duration of immunity

57
Q

Heterophile antigens

A

Exist in unrelated plants or animals but are identical to or closely related in structure so that antibody to one antigen will cross react with the other

58
Q

MHC Class I loci

A

Loci A, B, and C

59
Q

MHC Class II loci

A

DP, DR, DQ

60
Q

MHC Class III loci

A

Codes for C4A, C4B, C2, and B complement proteins

61
Q

MHC class I: endogenous or exogenous

A

Endogenous (viruses + cancer)

62
Q

MHC class II: endogenous or exogenous

A

exogenous (bacteria, fungus, + parasites)

63
Q

MHC Classes I and II are involved in _____________; they influence the antigens to which ________ respond.

A

Antigen recognition; T cells

64
Q

Class III is composed of secreted proteins that have an immune function, but they are:

A

not expressed on cell surfaces

65
Q

Where are genes coding for MHC molecules found

A

p arm of chromosome 6

66
Q

What is the order of the classical pathway?

A

C1qrs –> C4b2a –> C4b2a3b –> C5b –> C5b6789

67
Q

What is the order of the lectin pathway?

A

MBL/MASP –> C4b2a –> C4b2a3b –> C5b –> C5b6789

68
Q

What is the order of the alternative pathway?

A

C3 cleaved into C3b + B by water –> Factor D cleaves B to make C3bBbP –> C3bBbP3b –> C5b –> C5b6789

69
Q

What is the C3 and C5 convertase for the classical pathway?

A

C3: C4b2a
C5: C4b2a3b

70
Q

What is the C3 and C5 convertase for the lectin pathway?

A

C3: C4b2a
C5: C4b2a3b

71
Q

What is the C3 and C5 convertase for the alternative pathway?

A

C3: C3bBbP
C5: C3bBbP3b

72
Q

What are the down regulators of the classical pathway?

A

C1-INH
Factor I
C4BP
S protein

73
Q

What are the down regulators of the classical pathway?

A

C1-INH
Factor I
C4BP
S protein

74
Q

What are the down regulators for the alternative pathway?

A

Factor H
S protein

75
Q

2 IgG can activate complement. What distance must they both be from eachother in order to achieve this goal?

A

20-40 nm

76
Q

Which pathway is used for direct bacterial activation?

A

Lectin

77
Q

Which pathway includes Factor B, D, and P, and acts as an amplification loop, but can also act independently?

A

Alternative

78
Q

What complement deficiencies are associated with Lupus and recurrent infections?

A

C1 (q, r, or s)
C2
C4

79
Q

What complement deficiency is associated with Glomerulonephritis?

A

C3

80
Q

What complement deficiency is associated with Neisseria infections?

A

C5-C8

81
Q

What complement deficiency is associated with PNH?

A

DAF/MIRL

82
Q

What is the CH50 test?

A

Shows which dilution causes lysis of 50% of cells

83
Q

C5 monoclonal antibody

A

Eculizumab

84
Q

What is the end product of all of the complement pathways?

A

Lysis of invading cell via MAC

85
Q

What are the four functions of complement?

A

Opsonization
Increase vascular permeability
Recruit monocytes and neutrophils to area needed
Trigger secretion of immunoregulatory molecules to amplify immune response

86
Q

All complement factors are synthesized in the liver, EXCEPT? Where are they synthesized?

A

Factor D –> adipose tissue
C1 components –> intestinal epithelial cells

87
Q

What can initiate the classical pathway?

A

IgM/IgG bound to antigen
CRP bound to ligand
Viruses/mycoplasma/GNR/protozoa directly bound

88
Q

When C4/C2/C3 is cleaved, where does the other half go that is not involved in the convertases??

A

Pro-inflammation recruitment

89
Q

A ___________ of an MHC molecule is inherited from each parent.

A

HAPLOTYPE

90
Q

Class I MHC molecules are expressed on which cells?

A

All nucleated cells

91
Q

MHC Class I has highest expression on which cells?

A

Lymphocytes and myeloid cells

92
Q

Structure of MHC Class I

A

3 alpha subunits, 1 beta-2 microglobulin subunit

93
Q

Antigen Presenting Cells (examples)

A

B lymphs
Monocytes
Macrophages
Dendritic cells
Thymic epithelium

94
Q

Structure of MHC Class II

A

2 alpha and 2 beta subunits

95
Q

What T cell recognizes MHC Class I

A

CD8+ (Cytotoxic) to target viruses/cancer

96
Q

What T cell recognizes MHC Class II

A

CD4+ (T helper) to target bact/fung/parasites

97
Q

Which T helper class provides support in B cell differentiation?

A

Th2

98
Q

Class II MHC molecules are expressed on which cells?

A

APCs

99
Q

Which HLA allele is associated with Ankylosing spondylitis?

A

B27(+++)

100
Q

Which HLA allele is associated with Rheumatoid arthritis?

A

DR4(+)

101
Q

Which HLA allele is associated with type 2 diabetes?

A

DQ8(++), DQ2

102
Q

Which HLA allele is associated with celiac disease?

A

DQ2(+++), DQ8

103
Q

What specific stimuli are cytokines induced in response to?

A

Flagellin, bacterial lipopolysaccharides, other bacterial products, and ligation of cell-adhesion molecules

104
Q

Pleiotropy

A

One cytokine has many different actions

105
Q

Redundancy

A

Different cytokines have the same effects

106
Q

Synergy

A

Some cytokines enhance the effects of eachother

107
Q

Antagonism

A

Cytokines counteract eachother

108
Q

Which cytokines are associated with pro-inflammation?

A

IL-1, IL-6, TNF-alpha

109
Q

Which cytokines “wind down” the immune system?

A

IL1-RA, TGF-beta,

110
Q

Which cytokines are made by Th1?

A

IL-2 and IFN-gamma

111
Q

Which cytokines are made by Th2?

A

IL-4 and IL-10

112
Q

Which cytokines are made by monocytes/macrophage?

A

IL-1, IL1RA, TNF-alpha, IFN-a, IFN-b

113
Q

Which cytokines are made by lymphocytes?

A

IL-7, IL-6

114
Q

Which cytokines drive hematopoiesis?

A

EPO

115
Q

What is a “cytokine storm”?

A

Massive overproduction and dysregulation of cytokines, can lead to hypotension/fever/edema/organ failure/death.

116
Q

Roles of cytokines

A
  • Induce inflammation
  • Recruit effector cells (neut, monos)
  • Produce systemic effects (fever, incr APRs, hematopoiesis)
117
Q

Roles of cytokines

A
  • Induce inflammation
  • Recruit effector cells (neut, monos)
  • Produce systemic effects (fever, incr APRs, hematopoiesis)IL
118
Q

IL1RA

A

Anti-inflammatory effect

119
Q

Chemokines

A

Enhance motility and promote migration of many types of WBCs toward the source of the chemokine (chemotaxis)

120
Q

TGF-B

A

Induces antiproliferative activity in many cell types, helps down regulate the inflammatory response when no longer needed

121
Q

Th1 helps active ________. Th2 helps activate ________.

A

CD8+ cells
B cells

122
Q

What cytokine is associated with eosinophils and basophils?

A

Eosinophils: IL-5
Basophils: IL-3