Immunology Flashcards

1
Q

What is the acronym ACID with regard to types of hypersensitivity reactions?

A

A - anaphylactic, allergic, atopic
C - cell-mediated, cytotoxic
I - immune complexes
D - delayed

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

With regard to HLA, which are up-regulated and which are down-regulated in pregnancy?

A
Down-regulated = HLA-A and HLA-B
Up-regulated = HLA-E and HLA-G
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How does the placenta inhibit complement protein?

A

DAF, MCP and CD59 expressed on the placenta inhibit complement proteins

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

With regard to T-helper (Th) cells, which increase and which decrease in pregnancy?

A
Th1 = decreased, therefore rheumatoid improves in pregnancy
Th2 = increased, therefore SLE exacerbated during pregnancy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which Ig has a pentameter structure?

A

IgM

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

Which Ig’s have a monomer structure?

A

IgA, IgD, IgG, IgE

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

Which Ig has a dimer structure?

A

IgA - can have either a dimer or monomer structure

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

What are the 3 professional APC’s?

A

1) Dendritic cells
2) Macrophages
3) B-cells

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

Following potentially sensitising events, when should anti-D Ig be administered?

A

As soon as possible, always within 72 hours

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

When is anti-D Ig prophylaxis indicated at <12/40 gestation?

A

1) Ectopic pregnancy
2) Molar pregnancy
3) TOP
4) Uterine bleeding which is repeated and heavy or associated with abdominal pain

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

What are the potentially sensitising events beyond 12/40 gestation that require anti-D?

A

1) Amniocentesis
2) CVS
3) APH and PV bleeding
4) ECV
5) Abdominal trauma
6) Ectopic
7) Evacuation of molar pregnancy
8) IUD/stillbirth
9) Miscarriage
10) TOP
11) Delivery
12) In-utero interventions, e.g. surgery, lasers etc.

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

Which Ig crosses the placenta?

A

IgG

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

Which Ig is the first to be produced by the neonate?

A

IgM

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

Which Ig is passed through breast milk?

A

IgA

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

What are the common products of the the 3 complement pathways?

A

C3, cleaved to C3a and C3b

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

What is the role of C3b?

A

1) Opsonisation

2) Forms C5 convertase (with other proteins) which cleaves C5 to C5a and C5b

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

What does C5b do?

A

Recruits C6, C7, C8 and C9 to form MAC - membrane attack complex

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

What is an allograft?

A

An allograft is where tissue from a different individual of the same species is used - i.e. a foetus is a natural allograft

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

At what gestation does maternofetal IgG start?

A

Week 12

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

At what gestation does the fetus start producing IgM?

A

Weeks 10-11

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

What does Th1 produce?

A

TNF-alpha, IFN-y and IL-2 - therefore since Th1 is suppressed in pregnancy, these are all reduced during pregnancy

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

What does Th2 produce?

A

IL-4, IL-5, IL-9, IL-10 and IL-13 - since Th2 production increases during pregnancy, these also increase during pregnancy

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

What are some examples of attenuated vaccines?

A

1) MMR
2) Polio
3) BCG

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

What are some examples of inactivated vaccines?

A

1) Hep A
2) Pertussis
3) Influenza

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

What are some examples of toxoid vaccines?

A

1) Tetanus

2) Diptheria

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

What is an example of a subunit vaccine?

A

Hep B

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

What are examples of a type III hypersensitivity reaction?

A

1) SLE
2) Serum sickness
3) RA
4) Extrinsic allergic alveolitis
5) Post-strep glomerulonephritis

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

What is the innate immune system?

A

The immediate and non-specific response to attack

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

What is the adaptive immune system?

A

The more complex and specific response to antigens and generates immunological memory

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

What are the cells of the innate immune system?

A

Macrophages, neutrophils, natural killer cells

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

What are the cells of the adaptive immune system?

A

T-helper cells, B cells

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

What is the role of IgE?

A

Activates mast cells

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

At what gestation should a pregnant woman receive her whooping cough vaccination?

A

27-36 weeks

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

What are some examples of type I hypersensitivity reactions?

A

Anaphylaxis, atopy, allergic asthma

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

What are type I hypersensitivity reactions caused by?

A

IgE mediated degranulation of mast cells, triggered by antigen binding. Effects in <30 mins

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

What are some examples of type II hypersensitivity reactions?

A

Transfusion reaction, rhesus incompatibility

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

What are type II hypersensitivity reactions caused by?

A

Cytotoxic. Antigens cause IgM and IgG formation which bind to surface of target cells and then destroy it by complement. Effects 5-12 hours

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

What are type III hypersensitivity reactions caused by?

A

Immune-complex mediated. Effects 3-8 hours

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

What are some examples of type IV hypersensitivity reactions?

A

Contact dermatitis, chronic transplant rejection

40
Q

What are type IV hypersensitivity reactions caused by?

A

Delayed. T-helper cells release cytokines leading to macrophage and T cell accumulation. Effects 24-48 hours

41
Q

On which chromosome are the HLA genes found?

A

Chromosome 6

42
Q

What are the most efficient antigen-presenting cells (APC)?

A

Dendritic cells

43
Q

What are the different types of APCs?

A

Dendritic cells and macrophages

44
Q

From what and where are APCs derived?

A

Derived from monocytes produced by bone marrow

45
Q

What are some examples of type V hypersensitivity reactions?

A

Myasthenia gravis

Graves disease

46
Q

Which hypersensitivity reaction forms the basis of the Mantoux test?

A

Type IV

47
Q

What type of vaccine is varicella?

A

Attenuated

48
Q

Which Ig has the highest molecular weight?

A

IgM

49
Q

What is the mechanism of action of azathioprine?

A

Inhibition of nucleic acid synthesis in all mitotic cells

50
Q

Natural killer cells belong to what cell type?

A

Lymphocytes

51
Q

What 2 inflammatory mediators are released by both mast cells and platelets?

A

Histamine and serotonin

52
Q

What is the frequency of of lupus anticoagulant Abs in the general population?

A

2-5%

53
Q

What is the risk of fetal mortality with lupus anticoagulant Abs?

A

85-95%

54
Q

What type of cell congregates around the cervix to release collagenase?

A

Neutrophils

55
Q

What is the most abundant circulating phagocyte?

A

Neutrophils

56
Q

What are the two different receptor types found on the surface of NK cells?

A
  1. CD16 receptors

2. KIRs (i.e. killer cell immunoglobulin-like receptors) - they engage MHC molecules on target cells

57
Q

What are the three pathways that can activate complement?

A
  1. Classic pathway
  2. Alternative pathway
  3. Lectin pathway
58
Q

What are the two different types of CD4+ T cells?

A

Th1 and Th2

59
Q

What are the different types of cytokine?

A
  1. Interferons
  2. Interleukins
  3. Chemokines
  4. Growth factors
60
Q

What is an autograft?

A

Tissue transferred from one part of the body to another

61
Q

What is an isograft?

A

Tissue transferred between genetically identical individuals

62
Q

What is a xenograft?

A

Tissue transferred between two different species

63
Q

What are some examples of type III hypersensitivity reactions?

A

Persistent infection - e.g. le/prosy, viral hepatitis
Immune-mediated - e.g. SLE and RA
Inhalation of antigen - e.g. farmer’s lung, pigeon-fancier’s lung

64
Q

Rhesus D immunoglobin treatment utilises what class of antibody?

A

IgG

65
Q

Which is the only live vaccine recommended for people with HIV?

A

Measles

66
Q

Where in the body do T cells differentiate?

A

Thymus

67
Q

What does the Fab segment of the immunoglobulin determine?

A

Affinity/specificity of antibody for antigen

68
Q

What does the Fc segment of the immunoglobulin determine?

A

All other properties, e.g. ability to cross the placenta etc.

69
Q

Which immunoglobulin has the lowest molecular weight?

A

IgG

70
Q

What is the volume of a unit of packed red cells?

A

280+/-20ml

71
Q

What are the two arms of the adaptive immune system?

A
  1. Humoral immunity - antibody production

2. Cellular immunity

72
Q

What are the three types of immune tolerance?

A
  1. Central tolerance
  2. Peripheral tolerance
  3. Acquired tolerance
73
Q

Where does central tolerance occur?

A

Bone marrow and thymus

74
Q

What type of immune tolerance occurs in pregnancy?

A

Acquired tolerance

75
Q

Where is the complement system synthesised?

A

Liver

76
Q

What is the cause of hyperacute transplant rejection?

A

Pre-formed host antibodies (hence why it occurs so quickly)

77
Q

What is the trigger of the classical complement pathway?

A

Antibody trigger

78
Q

What is the trigger of the alternative complement pathway?

A

Antigen trigger

79
Q

What is the function of CRP?

A

It coats a pathogen to promote opsonization

Its gene is on chromosome 1

80
Q

What are the 3 types of lymphocytes?

A
  1. T cells
  2. B cells
  3. NK cells
81
Q

What are the different types of T cells?

A
  1. CD4 expressing T cells - i.e. Th1 and Th2 cells (MHC 2 only)
  2. CD8 expressing T cells - i.e cytotoxic and suppressor T cells (MHC 1 only)
  3. CD4 and CD8 expressing T cells
82
Q

Which part of the adaptive immune system do Th1 cells mediate?

A

Cellular immunity

83
Q

Which part of the adaptive immune system do Th2 cells mediate?

A

Humoral immunity

84
Q

What do B cells differentiate into?

A

Plasma cells - secret antibodies

Memory cells

85
Q

What is contained within a lymph node cortex?

A

Outer (nodular) cortex - contains B cells

Inner (juxtamedullary) cortex - contains T cells

86
Q

What is contained within a lymph node medulla?

A

Medullary cord - contains plasma and T cells

Medullary sinuses - contains histiocytes and reticular cells

87
Q

What is the structure of immunoglobulins?

A

2 heavy and 2 light chains bound by disulphide bonds

88
Q

What proportion of fetuses develop congenital heart block in the presence of anti-Ro/La positive mothers?

A

2% - permanent

89
Q

What proportion of fetuses develop cutaneous neonatal lupus in the presence of anti-Ro/La positive mothers?

A

5% - transient

90
Q

What is the perinatal mortality rate of congenital heart block?

A

19%

91
Q

Which markers may indicate ovarian sex cord stromal tumours?

A

Calretinin

Inhibin

92
Q

Which markers may indicate mucinous ovarian tumours?

A

Ca 19-9

CK20

93
Q

What is responsible for the destruction of the myelin sheaths seen in MS?

A

Cellular immunity - Th1 cells

94
Q

What are the 2 immunological interfaces in human pregnancy?

A
  1. Extra-villous cytotrophoblast/decidua - in early pregnancy
  2. Syncytiotrophoblast/maternal blood - in late pregnancy
95
Q

What are the immunological characteristics of the syncytiotrophoblast?

A
  1. NO MHC1 or MHC2 antigens expressed
  2. NO stimulation of cytotoxic activity
  3. NO NK cell activity
96
Q

When does maternal IgG transfer to fetus peak?

A

32 weeks