Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

SFM Exam 2 > 17: Hypersensitivity > Flashcards

17: Hypersensitivity Flashcards

1
Q

Type I hypersensitivity: primary exposure to allergen: 5 Steps

A
  1. Th2 cell activation (via IL-4)
  2. B cell activation
  3. IgE production
  4. IgE binds FCER (CD23) on mast cells
  5. Pt now sensitized to allergen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Type I hypersensitivity: subsequent allergen exposures: 2 Steps

A
  1. Ag cross-linking of IgE on mast cells -> mast cell activation
  2. Mast cells release inflammatory mediators
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Atopy

A

Genetic tendency to develop allergic disease

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

Five inflammatory mediators released by mast cells

A

Cytokines, histamine, proteases, prostaglandins, leukotrienes

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

Immediate vs late phase reaction of type I hypersensitivity

A

Immediate: within minutes - vasodilation and edema

Late phase: 2-24hrs later - inflammatory infiltrate rich in eosiniohils, neutrophils, and T cells

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

Three examples of type I hypersensitivities

A
  1. Allergies
  2. Asthma
  3. Anaphylaxis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Three major mediators of asthma

A

Mast cells, prostaglandins, leukotrienes

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

Asthma vs anaphylaxis

A

Asthma: local reaction
Anaphylaxis: systemic

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

Two cell types involved in anaphylaxis

A

Mast cells, basophils

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

3 goals of allergen-SIT

A
  1. Induce peripheral T cell tolerance by generating Tregs
  2. Increase threshold for mast cell and basophil activation by allergens
  3. Decrease IgE-mediated histamine release
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Type II hypersensitivity

A

Abs bind tissue Ags -> cause complement dependent tissue injury

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

What cells release inflammatory mediators in type II hypersensitivity

A

Neutrophils and macrophages

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

11 Examples of Type II Hypersensitivity

A
  1. ABO blood transfusion reaction
  2. Hemolytic disease of Newborn
  3. Drug-induced hemolytic anemia
  4. Autoimmune hemolytic anemia
  5. Autoimmune thrombocytopenic purpura
  6. Goodpastures syndrome
  7. Graves’ disease
  8. Myasthenia gravis
  9. Pemphigus vulgaris
  10. Pernicious anemia
  11. Rheumatic fever
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do we form Abs against blood group Ags that we dont have?

A

There are sugars that are identical (or v similar) to blood group Ags in foods or microbes, which we form reactions to to produce Abs

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

Hemolytic disease of newborn

A

The Rh thing

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

Three types of drug-induced hemolytic anemia and treatment used

A
  1. Penicillin: no tx needed
  2. Quinidine: immunosuppression/plasmapheresis
  3. Methyldopa: same as quinidine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is targeted in autoimmune thrombocytopenic purpura?

A

Platelet membrane proteins

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

What is targeted in goodpastures syndrome?

A

Proteins in kidney glomeruli and lung alveoli

19
Q

Grave’s disease

A

Ab-mediated stimulation of TSH receptors

20
Q

Myasthenia gravis

A

Ab inhibits Ach receptor, causing muscle weakness, paralysis, and ptosis

21
Q

Pemphigus vulgaris

A

Abs target intercellular epidermal junctions -> vesicles on skin

22
Q

Pernicious anemia

A

Ab neutralizes intrinsic factor -> decreased vitamin B12 absorption

23
Q

Rheumatic fever

A

Ab targets strep cell wall, which cross-reacts with myocardial Ags

24
Q

Type III hypersensitivity

A

Circulating/soluble ICs form -> deposit in vessels -> complement activation

25
Q

Five examples of type III hypersensitivity

A
  1. SLE
  2. Polyarteritis nodosa
  3. Post-strep glomerulonephritis
  4. Serum sickness
  5. Arthus reaction
26
Q

SLE Ab specificity

A

Ab specific for DNA or nucleoproteins

27
Q

Polyarteritis nodosa

A

Ab specific for microbial agents -> vasculitis

28
Q

Post strep glomerulonephritis

A

Ab specific for strep cell wall Ag -> nephritis

29
Q

Serum sickness and arthus reaction specificity

A

Ab specific for various protein Ags

30
Q

Serum sickness vs arthus reaction

A

Serum sickness: systemic + clinical or experimental

Arthus: local + experimental

31
Q

Serum sickness

A

Antiserum injected into blood -> Fc receptors on endothelium bind antitoxin Ab that has reacted with toxoid -> complement activation

32
Q

Arthus reaction

A

SubQ administration of protein Ag to a previously immunized animal -> IC formation at injection site -> vasculitis and complement cascade

33
Q

When do type IV hypersensitivities develop?

A

24-48 hours after Ag exposure

34
Q

Four major cell players in type IV hypersensitivity

A

Th1, Th17, CTLs, macrophages

35
Q

Six examples of type IV hypersensitivity

A
  1. MS
  2. RA
  3. DM I
  4. IBD / Crohn’s
  5. Chronic infection
  6. Contact dermatitis / sensitivity
36
Q

MS

A

T cells target myelin proteins -> demyelination in CNS

37
Q

RA

A

T cells target Ags in joints

38
Q

DM I

A

T cells target pancreatic islet Ags

39
Q

Crohn’s and IBD

A

T cells target unknown Ag linked to intestinal microbes

40
Q

Chronic infection

A

T cells target microbial infection -> chronic inflammation

41
Q

Contact sensitivity / dermatitis

A

T cells target modified skin proteins

42
Q

Most common contact allergen

43
Q

PPD

A

Purified protein derivative: protein Ag of mycobacterium tuberculosis that elicits a DTH reaction called tuberculin reaction in previously infected individuals

SFM Exam 2 (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions