T7 Infection, Immunity and Inflammation Flashcards Preview

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Flashcards in T7 Infection, Immunity and Inflammation Deck (101)
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1
Q

What are the most common cells outside the blood?

A

Mast cells

2
Q

What is viral tropism?

A

How only specific viruses can be taken up by specific tissues

3
Q

Where and how are self-reactive T cells removed?

A

By negative selection in the thymic medullary cells

4
Q

Where is antigen presented to T cells?

A

On antigen binding grooves

5
Q

Which ligand does NOD-1 recognise?

A

y-glutamyl diaminopimelic acid

6
Q

How do CD4 T cells respond to IL-4?

A

By differentiating into Th2 cells

7
Q

Where are nTregs produced?

A

In the thymus

8
Q

Which ligand does TLR-1 dimer and TLR2/6 dimer recognise?

A

Peptidoglycans, lipoproteins, mycobacteria, GP1, zymosan

9
Q

Which T cells recognise MHC class I?

A

CD8

10
Q

Give an example of gram negative cocci.

A

Gonorrhoea, meningococcal meningitis causing

11
Q

What do CD4 and Th2 secrete to help B-cells?

A

IL-4, IL-13

12
Q

Which cells are involved in the tuberculin response of type IV hypersensitivity?

A

Th1, IFNy and IL-2 attract macrophages

13
Q

How do CD4 T cells respond to IL-12?

A

By differentiating into Th1 cells

14
Q

Give an example of gram positive rod.

A

Spore forming e.g. antharax, tetanus

15
Q

What are acid-fast bacteria? Give an example.

A

Do not stain, have waxy mycolic acids in cell wall. E.g. mycobacterium tuberculosis.

16
Q

What does the alternate system of complement recognise?

A

The pathogen

17
Q

Give an example of gram positive cocci.

A

Staphycoccus aureus, streptococci pneumoniae, enterococci, strep. A, B & C

18
Q

What is suppurative inflammation?

A

Pus is present

19
Q

What do CD4 and Treg secrete to inhibit immune response?

A

TGF-B, IL-10

20
Q

Which ligand does TLR-5 recognise?

A

Flagellin

21
Q

What do the cytokines IL-12 and TNFa mediate?

A

Fever, macrophage activation, CD4 T-cell differentiation

22
Q

What happens in type II hypersensitivity?

A

IgG and IgM activate complement cascade, releasing C3a and C5a, recruiting inflammatory cells and allowing killer cell attack

23
Q

Which antibody will be dominant when reacting to a pathogen never seen before?

A

IgM

24
Q

Which out of gram positive and gram negative bacteria survive drying better?

A

Gram positive

25
Q

Which MHC is expressed on all nucleated cells?

A

Class I

26
Q

When is a T cell activated?

A

When CD4 or 8, MHC and TCR bind and CD28 binds to CD86

27
Q

What do T cell receptors consist of?

A

alpha beta or gamma delta chains

28
Q

What happens in type I hypersensitivity?

A

Mast cell degranulation due to cross linking of IgE activated by histamine, tryptases, prostaglandins, leukotrienes and cytokines

29
Q

Which cells make interferons?

A

Virally infected cells

30
Q

Describe inoculation

A

Virus directly enters blood

31
Q

What kind of selection does a thymocyte undergo for MHc affinity?

A

Positive selection

32
Q

Which antigens are presented on MHC class II?

A

Exogenous antigens

33
Q

What lineage do natural killer cells have?

A

Lymphoid

34
Q

How is diversity of antibody specificity achieved?

A

By random genetic recombination

35
Q

Is adenovirus RNA or DNA based?

A

DNA

36
Q

What genes are heavy chains made of?

A

V, J and D genes

37
Q

Which antigens are presented on MHC class I?

A

Endogenous antigens

38
Q

Why does antibody specificity vary?

A

Due to differences in VH and VL sequence

39
Q

What does absence of recombination activity in receptor formation in the adaptive immune system cause?

A

SCID (severe combined immune deficiency)

40
Q

What cells do CD4 and Th17 activate?

A

Neutrophils

41
Q

Which cells are involved in the asthma response of type IV hypersensitivity?

A

Th2, IL-4, IL-8,IL-13 attract eosinophils

42
Q

Is hepatitis B virus RNA or DNA based?

A

DNA

43
Q

Give an example of gram negative rod.

A

E. coli, salmonella, anaerobes, legionella, haemophilus, shigella, brucella, proteus, pseudomonas

44
Q

What does a T cell do when it is activated by a virally infected cell?

A

Causes the cell to die by apoptosis

45
Q

What is membranous inflammation?

A

Membrane produced over surface of inflamed tissue

46
Q

Where does affinity maturation of B cells occur?

A

In B cell follicles

47
Q

What does detection of PAMPs cause?

A

Migration of antigen presenting cells to secondary lymphoid organs

48
Q

Which out of gram positive and gram negative bacteria has teichoic acid in cell wall?

A

Gram positive

49
Q

What are the PRRs in cell membranes?

A

Toll like

50
Q

Which out of gram positive and gram negative bacteria produces spores?

A

Gram positive

51
Q

What produces the chemokine IL-8?

A

Macrophages and endothelial cells

52
Q

Which cytokines do natural killer cells respond to?

A

TNFa and IL-12

53
Q

Which ligand does TLR-9 recognise?

A

Unmethylated CpG DNA

54
Q

Which out of gram positive and gram negative bacteria has a cell membrane?

A

Gram negative

55
Q

Is herpes virus RNA or DNA based?

A

DNA

56
Q

Describe the hepatitis B virus

A

Hepadnavirus ds DNA genome, icosahedral symmetry with envelope

57
Q

Describe the influenza virus

A

Orthoxovirus ss- RNA genome helical symmetry with envelope

58
Q

Is picornavirus RNA or DNA based?

A

RNA

59
Q

What genes are light chains made of?

A

V and J genes

60
Q

Which cells are destroyed by the HIV virus?

A

CD4 T cells

61
Q

What are the type-1 interferons?

A

IFNa and IFNb

62
Q

What is the mechanism of fever?

A

Increased cytokine production, reset set point of hypothalamus. PGE2 produced by hypothalamus.

63
Q

What do the cytokines IL-1 and IL-6 mediate?

A

Inflammation and fever

64
Q

How do CD4 T cells respond to IL-6 and TGF-B?

A

By differentiating into Th17 cells

65
Q

Which interferon do natural killer cells produce?

A

IFNy

66
Q

Which genes encode MHC?

A

A, B and C

67
Q

What does the classical system of complement recognise?

A

Antigen:Antibody complex

68
Q

What is complement responsible for?

A

Creation of membrane attack complex

69
Q

What are the 6 stages of lytic viral infection?

A
  1. Replication
  2. Assembly of capsids with new nucleic acid
  3. Release of capsid from cell
  4. Binding of capsid to host cell
  5. Penetration of host cell by membrane fusion
  6. Capsids release DNA/RNA
70
Q

Describe the Varicella zoster virus

A

Herpse virus ds DNA genome, icosahedral symmetry with envelope

71
Q

Which immunoglobulin is found as a dimer?

A

IgA

72
Q

Describe the HIV virus

A

ss+ RNA, icosahedral symmetry with envelope

73
Q

Which immunoglobulin is used in a parasitic infection?

A

IgE

74
Q

Is retrovirus RNA or DNA based?

A

RNA

75
Q

What happens in type III hypersensitivity?

A

IgG activates complement cascade, releasing C3a and C5a, recruiting inflammatory cells and allowing killer cell attack in serum

76
Q

What happens in toxic shock syndrome?

A

Toxins are produced by S. aureus or pyrogens called superantigens which allow binding of MHC cells with T cell receptors meaning up to 20% of T cells are activated against host cells causing multi-organ failure

77
Q

What do CD4 and Th1 secrete to target intracellular pathogens?

A

IFNy and IL-2

78
Q

Where are collectins found?

A

In serum

79
Q

What does the membrane attack complex form from?

A

C5b, C6, C7, C8, C9

80
Q

How do CD4 T cells respond to IL-2 and TGF-B?

A

By differentiating into Treg cells

81
Q

When are interferons IFNa and IFNb produced?

A

In response to virally infected cells

82
Q

Which ligand does NOD-2 recognise?

A

Muramyl dipeptide

83
Q

What does C3b cause?

A

Production of the membrane attach complex

84
Q

What does the MB lectin system of complement recognise?

A

Mannose on pathogen

85
Q

Which antibody will be dominant when reacting to a pathogen encountered before?

A

IgG

86
Q

What kind of pathogen is a Helminth?

A

A parasite

87
Q

What are digestive enzymes kept inside in a phagocyte?

A

Lysosomes

88
Q

Which genes code for the constant region of antibody?

A

C genes

89
Q

Which region of antibody determines its function?

A

The constant region

90
Q

Which T cells recognise MHC class II?

A

CD4

91
Q

Which ligand does TLR-4 dimer and CD14 recognise?

A

LPS on gram negative bacteria

92
Q

What domains does a T cell receptor have?

A

aC, bC, aV, bV

93
Q

How do CD4 and Th1 activate CD8?

A

Via IFN-y and IL-2

94
Q

Where and when are cell adhesion molecules expressed?

A

On epithelium in inflammation and always on WBCs

95
Q

Which cells mediate type I diabetes?

A

Mainly T cells

96
Q

Which cells mediate allergy?

A

CD4 and Th2 cells

97
Q

What do CD4 and Th17 secrete to target extracellular bacteria and fungi?

A

IL-17, IL-21

98
Q

Which out of gram positive and gram negative bacteria has endotoxin in cell wall?

A

Gram negative

99
Q

Why do T cells not destroy self cells?

A

Self reactive cells are inactivated before maturation

100
Q

Which ligand does TLR-3 recognise?

A

dsRNA

101
Q

Which immunoglobulin is effective at activating complement?

A

IgM