Hypersensitivity and Autoimmune disease Flashcards

1
Q

What are the types of hypersensitivity reactions?

A

Immediate (Type I)
Antibody-mediated (Type II)
Immune complex-mediated (Type III)
Delayed-type hypersensitivity (Type IV)

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

What are the immune mechanisms involved in a type I reaction?

A

Activation of Th2 cells resulting in the production of IgE which in turn binds to FceR on mast cells, basophils and eosinophils

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

What are the mechanisms of tissue injury behind a type I reaction?

A

Immediate reaction:
Degranulation and release of vasoactive amines (ie. histamine) and proteases

Late-phase reaction:

  1. Synthesis and secretion of prostaglandins and leukotrienes
  2. Cytokine-induced inflammation and leukocyte recruitment
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the immune mechanisms involved in a type II reactions?

A

IgM and IgG against surface (cell surface or extracellular matrix)

Antibodies on top of tissue

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

What are mechanisms of tissue injury behind a type II reaction?

A

Complement mediated (cytotoxic):

  1. Opsonization and enhances phagocytosis
  2. Recruitment and activation of inflammatory cells

Non-cytotoxic:
Change in physiologic behavior of a cell

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

What are the immune mechanisms involved in a type III reaction?

A

Deposition of immune complexes comprised of IgM or IgG and soluble antigen

Complex inside tissue

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

What are the mechanisms of tissue injury behind a type III reaction?

A

Complement mediated recruitment and activation of inflammatory cells resulting in some combination of arthritis, vasculitis, and/or nephritis

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

What are the immune mechanisms involved in a type IV reaction?

A

Inflammatory cytokines, IFN-gamma and IL-17, produced by CD4+ Th1 and Th17 cells, respectively

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

What are the mechanisms of tissue injury behind a type IV reaction?

A

Only reaction due to T cells

Cytokine-mediated tissue damage:

  1. IFN-gamma activation of macrophage
  2. IL-17 recruitment and activation

Direct killing:
CTL-mediated cellular death

CD8+ CTLs (T-cell-mediated cytolysis):
Direct target killing, cytokine-mediated inflammation

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

What are some examples of Type I hypersensitivity?

A
Allergic rhinitis
Systemic anaphylaxis
Food allergies
Wheal and flare
Asthma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the allergens that cause allergic rhinitis?

A

Trees, grasses, dust, cats, dogs, mites

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

What are the clinical findings of allergic rhinitis?

A

Edema, irritation, mucus in nasal mucosa

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

What are the allergens that cause systemic anaphylaxis?

A

Insect stings, drug reactions

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

What are the clinical findings of systemic anaphylaxis?

A

Bronchial and tracheal constriction, complete vasodilation and death

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

What are the allergens that cause food allergies

A

Milk, eggs, fish, cereals, grains

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

What are the clinical findings of food allergies?

A

Hives and gastrointestinal problems

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

What is the wheal and flare?

A

In vivo skin testing for allergies

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

What are the clinical findings of the wheal and flare

A

Local skin edema, reddening, vasodilation of vessels

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

What are the allergens that cause asthma?

A

Inhaled materials

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

What are the clinical findings of asthma?

A

Bronchial and tracheal constriction, edema, mucus production, massive inflammation

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

What are examples of Type II hypersensitivity?

A
Autoimmune hemolytic anemia (HDNB)
Acute rheumatic fever
Goodpasture syndrome
Transfusion reaction
Autoimmune thrombocytopenia purpura
Myasthenia gravis
Graves disease
Type II (insulin resistant) diabetes
Pernicious anemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the examples of Type III hypersensitivity?

A
Systemic lupus erythematosus
Poststreptococcal glomerulonephritis
Arthus reaction
Serum sickness
Polyarteritis nodosa
Diffuse systemic sclerosis
Limited scleroderma
Sjorgren syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the antigen involved in systemic lupus erythematosus?

A

dsDNA
Sm
Other nuceloproteins

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

What are the clinical manifestations of systemic lupus erythematosus?

A

Nephritis
Arthritis
Vasculitis
Butterfly facial rash

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

What is the antigen involved in poststreptococcal glomerulonephritis?

A

Steptococcal cell wall Ags (may be “planted” in glomerular basement membrane)

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

What are the clinical manifestations of poststreptococcal glomerulonephritis?

A

Nephritis

“lumpy-bumpy” deposits

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

What are the clinical manifestations of poststreptococcal glomerulonephritis?

A

Nephritis

“lumpy-bumpy” deposits

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

What is the antigen involved in Arthus reaction?

A

Any injected protein

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

What are the clinical manifestations of Arthus reaction?

A

Local pain and edema

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

What is the antigen involved in serum sickness?

A

Various proteins

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

What are the clinical manifestations involved in serum sickness?

A

Arthritis
Vasculitis
Nephritis

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

What is the antigen involved in polyarteritis nodosa?

A

Hepatitis B virus Ag

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

What is the clinical manifestation of polyarteritis nodosa?

A

Systemic vasculitis

34
Q

What is the antigen involved in Diffuse systemic sclerosis?

A

Antibodies to DNA topoisomerase 1

35
Q

What is the antigen involved in Limited scleroderma (CREST)?

A

Antibodies to centrometric proteins

36
Q

What is the antigen involved in Sjorgren syndrome?

A

Antibodies to ribonucloproteins

37
Q

What is the target antigen of autoimmune hemolytic anemia (HDNB)?

A

RBC membrane proteins (Rh, I Ags)

38
Q

What is the mechanism of pathogenesis of autoimmune hemolytic anemia (HDNB)?

A

Opsonization
Phagocytosis
complement-mediated destruction of RBCs

39
Q

What are the clinical manifestations of autoimmune hemolytic anemia (HDNB)?

A

Hemolysis and anemia

40
Q

What is the target antigen for acute rheumatic fever?

A

Streptococcal cell-wall Ag; Ab cross-reacts with myocardial Ag

41
Q

What is the mechanism of pathogenesis of acute rheumatic fever?

A

Inflammation and macrophage activation

42
Q

What are the clinical manifestations acute rheumatic fever?

A

Myocarditis and arthritis

43
Q

What is the target antigen for goodpasture syndrome?

A

Type IV collagen in basement membranes of kidney glomeruli and lung alveoli

44
Q

What is the mechanism of pathogenesis of goodpasture syndrome?

A

Complement and Fc-receptor mediated inflammation

45
Q

What are the clinical manifestations of goodpasture syndrome?

A

Nephritis
Lung hemorrhage
Linear Ab deposits

46
Q

What is the target antigen for transfusion reaction?

A

ABO blood glycoproteins

47
Q

What is the mechanism of pathogenesis of transfusion reaction?

A

AgM isohemagglutinins formed naturally in response to normal bacterial flora cause opsonization + complement activation

48
Q

What are the clinical manifestations of transfusion reaction?

A

Hemolysis

49
Q

What is the target antigen for autoimmune thrombocytopenia purpura?

A

Platelet membrane proteins

50
Q

What is the mechanism of pathogenesis of autoimmune thrombocytopenia purpura?

A

Ab-mediated platelet destruction through opsonization and complement activation

51
Q

What are the clinical manifestations of autoimmune thrombocytopenia purpura?

A

Bleeding

52
Q

What is the target antigen for myasthenia gravis?

A

Acetylcholine receptors

53
Q

What is the mechanism of pathogenesis of myasthenia gravis?

A

Ab inhibits acetylcholine binding, downmodulates receptors

54
Q

What are the clinical manifestations of myasthenia gravis?

A

Muscle weakness and paralysis

55
Q

What is the target antigen for graves disease?

A

TSH receptor

56
Q

What is the mechanism of pathogenesis of graves disease?

A

Ab-mediated stimulation of TSH receptors

57
Q

What are the clinical manifestations of graves disease?

A

Hyperthyroidism followed by hypothyroidism

58
Q

What is the target antigen of type II diabetes?

A

Insulin receptors due to type II diabetes being insulin resistant

59
Q

What is the mechanism of pathogenesis of type II diabetes?

A

Ab-inhibits binding of insulin

60
Q

What are the clinical manifestations of type II diabetes?

A

Hyperglycemia

61
Q

What is the target antigen for pernicious anemia?

A

Intrinsic factor of gastric parietal cells

62
Q

What is the mechanism of of pathogenesis of pernicious anemia?

A

Neutralization of intrinsic factor, decreased absorption of vitamin B12

63
Q

What are the clinical manifestations of pernicious anemia?

A

Abnormal erythropoiesis anemia

64
Q

What are the examples of Type IV hypersensitivity?

A
Tuberculin test
Contact dermatitis 
Hashimoto thyroiditis
Multiple sclerosis 
Reheumatoid arthritis
Insulin-dependent diabetes mellitus (type I)
Guillain-Barre syndrome
Celiac disease
Crohns disease
65
Q

What is the specificity of pathogenic T cells in tuberculin test?

A

PPD (tuberculin and mycolic acid)

66
Q

What are the clinical manifestations of the tuberculin test?

A

Indurated skin lesion (granuloma)

67
Q

What is the specificity of pathogenic T cells in contact dermatitis?

A

Nickel
Poison ivy/oak catechols
Hapten/carrier

68
Q

What are the clinical manifestations of contact dermatitis?

A

Vesicular skin lesion
Pruritus
Rash

69
Q

What is the specificity of pathogenic T cells in hashimoto thyroiditis?

A

Unknown Ag in thyroid

70
Q

What are the clinical manifestations of hashimoto throiditis?

A

Hypothyroidism

71
Q

What is the specificity of pathogenic T cells in multiple sclerosis?

A

Myelin basic protein

72
Q

What are the clinical manifestations of multiple sclerosis?

A

Progressive demyelination
Blurred vision
Paralysis

73
Q

What is the specificity of pathogenic T cells in rheumatoid arthritis?

A

Unknown Ag in joint synovium (type III collagen?)

74
Q

What are the clinical manifestations of rheumatoid arthritis?

A

Rheumatoid factor (IgM against Fc region of IgG)
Alpha-cyclic citrullinated (alpha-CCP)
Chronic arthritis
Inflammation
Destruction of articular cartilage and bone

75
Q

What is the specificity of pathogenic T cells in type I diabetes?

A

Islet-cell antigens
Insulin
Glutamic acid decarboxylase
Others

76
Q

What are the clinical manifestations of type I diabetes?

A
Chronic inflammation and destruction of beta cells
Polydipsia
Polyuria
Polyphagia
Ketoacidosis
77
Q

What is the specificity of pathogenic T cells of Guillain-Barre syndrome?

A

Peripheral nerve myelin or gangliosides

78
Q

What are the clinical manifestations of Guillain-Barre syndrome?

A

Ascending paralysis and peripheral nerve demyelination

79
Q

What is the specificity of pathogenic T cells of celiac disease?

A

CD4+ cells- gliadin
CD8+ cells
HLA class I-like molecule expressed during stress

80
Q

What are the clinical manifestations of celiac disease?

A

Gluten-sensitive enteropathy

81
Q

What is the specificity of pathogenic T cells of crohn disease?

A

Unknown Ag, commensal bacteria?

82
Q

What are the clinical manifestations of crohn disease?

A

Chronic intestinal inflammation due to Th1 and Th17 cells and obstruction