Brainscape's Knowledge GenomeTM

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


See full index

Supporting Life > Hypersensitivity > Flashcards

Hypersensitivity Flashcards

1
Q

What is T1 hypersensitivity

A

Immediate hypersensitivity (allergy anaphylaxis and atopy)

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

What is T1 mediated by

A

IgE-mast cells

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

Describe pathway of T1 hypersensitivity

A 
DC->antigen activates Th2 cells->expresses Il-4, IL-13, Il-5íIgE class switching in B cells->binds to IgE receptor on mast cells->sensitisation 
Cross-linking of 2 adjacent IgE molecules->degranulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What does Il-13 do

A

Increases mucus hypersecretion

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

What does Il-5 do

A

Activate eosinophils

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

What is the role of prostaglandisn

A

Increase vascular permeability

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

What is the role of leukotrienes

A

Smooth muscle contraction

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

What is the role of cytokine

A

Vasodilation, systemic anaphylaxis

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

What is the role of histamine in mast cells

A

increased vascular permeability, smooth muscle contraction, vasodilation, vascular leak (wheal +flair), bronchoconstriction, intestinal hypermobility

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

What is the role of tryptase

A

tissue remodelling, increased mucus secretion

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

List common allergens

A

Inhaled: pollens, spores, dander, dust mite
Ingested: peanut, egg, fruits, sesame
Venoms: bees, wasp stings and bites (Hymenoptera) - proteins present in venom and saliva
Drugs: abx, chemotherapeutics

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

How are allergen responses different to microbe responses

A

Do not induce macrophages/dendritic cells

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

What is the role of eosinophil

A

Activated by IL-5->release granules->tissue damage

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

What are the symptoms of T1 hypersensitivty

A

Lung - asthma ,wheezing
Nose - rhinitis, sneezing, runny nose
Eye - conjunctivitis
Skin - atopic dermatitis
Gut - food allergy
Skin prick test >3mm wheal through leakage of plasma and protein, vasodilation and congestion
Lab: total IgE (>100 IU/mL), specific IgE raised (e.g. radio-allergosorent test), tryptase levels but these are transient

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

What is T2 hypersensitivty

A

Antibody mediated

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

What causes T2 hypersensitivity

A

IgM, IgG antibodies against cell surface/ECM
Complement-mediated
Binding of Ab to Ag on cells->activate complement and recruit immune cells

17
Q

What are the 3 types of T2 hypersensitivty

A

Complement activation and opsonisation -> phagocytosis
Complement and Fc receptor mediated inflammation
No cell/tissue injury

18
Q

What are examples of complement action, opsonisation T2 hypersensitivity

A

Autoimmune haemolytic anaemia, autoimmune thrombocytopenic purpura, haemolysis in transfusion reaction

19
Q

What are examples of complement and Fc receptor mediated inflammation

A

neutrophil and macrophages binding of phagocytes to complement receptors and Fc receptors. Glomerulonephritis, vasculitis caused by ANCA

20
Q

What are examples of no cell/tissue injury T2 hypersensitivity

A

Grave’s disease (TSH receptors - increases production of TSH)
Insulin resistant diabetes
Myasthenia gravis (Ab binding to Ach receptor, creating muscular weakness)

21
Q

What is T3 hypersensitivty

A

Immune complex mediated
Soluble immune complexes antigen-IgM or antigen IgG
Activation of complement, recruit of neutrophils and macrophages
Pathologic features reflect the site of deposition -> multiple tissues

22
Q

What is the serum sickness modle

A

As antigen goes down in blood, antibodies start being produced. Complexes are produced. These small complexes are not phagocytosed can accumulate

23
Q

What are examples of T3 hypersensiviity

A 
SLE, nephritis, arthritis, vasculitis
Polyarteritis nodosa (HepB Ag-Ab): vasculitis
Poststreptococcal glomerulonephritis (Streptococcal Ag-Ab): nephritis
24
Q

What is T4 hypersensitivity

A

Cell mediated (delayed)
CD4 and CD8 cells. Cell killing and cytokine mediated inflammation
24-48 hour
Antibody-independent

25
Q

What are the two types of T4 hypersensitivtiy

A

Cytokine mediated inflammation and T cell mediated cytotoxcicity

26
Q

What is cytokine mediated inflamamtion

A

APC presents Ag to T cell -> activation (Th1, Th17, Th2 -> T cell secrete cytokines -> inflammation

27
Q

What are examples of cytokine mediated inflammation

A

IBD: Crohn’s (Th1/Th17), UC (TH2)
Contact sensitivity (ni2+)
Asthma

28
Q

What is T cell mediated cytotoxicity

A

CD8 T cell directly kill tissue cells

29
Q

What are examples of T cell mediated cytotoxicty

A

Autoimmune myocarditis: myosin heavy chain protein

T1DM: destruction of islet cells

Supporting Life (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions