Allergy

Question 1

What does the term atopy mean?

Answer 1

• when an individual is more susceptible to develop allergies

Question 2

In an allergic reaction there are 2 phases, acute and chronic. In the acute phase which antibody is associated with this type I hypersensitivity?

1 - IgA
2 - IgE
3 - IgM
4 - IgD

Answer 2

2 - IgE

Question 3

In an allergic reaction there are 2 phases, acute and chronic. In the acute phase IgE is secreted in response to the allergen (antigen). What cell do these antibodies then bind with and then activate resulting in degranulation?

1 - neutrophils
2 - basophils
3 - eosinophils
4 - mast cells

Answer 3

4 - mast cells

- bind to the Fc epsilon receptor on mast cells

Question 4

In an allergic reaction there are 2 phases, acute and chronic. In the acute phase IgE is secreted in response to the allergen (antigen). The IgE antibodies are able to bind with the Fc epsilon receptor on mast cells, resulting in degranulation. What key inflammatory mediator is release from the mast cells that is key in allergies?

1 - TNF-a
2 - histamines
3 - IL-6
4 - NF-KB

Answer 4

2 - histamines

Question 5

There is a long list of factors which increase the risk of atopy. One that has received a lot of interest is the hygiene hypothesis. What is the hygiene hypothesis?

Answer 5

• the use of clean procedures limits exposure to microorganisms and antigens at an early age
• early exposure to a range of microorganisms and antigens reduces the risk of atopy

Question 6

In an allergic reaction there are 2 phases, acute and chronic. In the acute phase IgE is secreted in response to the allergen (antigen). The IgE antibodies are able to bind with the Fc epsilon receptor on mast cells, resulting in degranulation and the release of the key inflammatory mediator histamine. What 2 other inflammatory mediators are produced as a results of histamine release from mast cells?

1 - leukotrienes and TNF-a
2 - leukotrienes and prostaglandins
3 - prostaglandins and TNF-a
4 - prostaglandins and IL-6

Answer 6

2 - leukotrienes and prostaglandins

Question 7

In an allergic reaction there are 2 phases, acute and chronic. In the acute phase IgE is secreted in response to the allergen (antigen). The IgE antibodies are able to bind with the Fc epsilon receptor on mast cells, resulting in degranulation and the release of the key inflammatory mediator histamine. What affect does degranulation of mast cells have on the GI tract?

Answer 7

• increased fluid secretions and peristalsis

- diarrhoea and vomitting

Question 8

In an allergic reaction there are 2 phases, acute and chronic. In the acute phase IgE is secreted in response to the allergen (antigen). The IgE antibodies are able to bind with the Fc epsilon receptor on mast cells, resulting in degranulation and the release of the key inflammatory mediator histamine. What affect does degranulation of mast cells have on the respiratory tract?

Answer 8

• histamine binds H1 receptors

- smooth muscle of bronchi contract and increase difficulty breathing

Question 9

In an allergic reaction there are 2 phases, acute and chronic. In the acute phase IgE is secreted in response to the allergen (antigen). The IgE antibodies are able to bind with the Fc epsilon receptor on mast cells, resulting in degranulation and the release of the key inflammatory mediator histamine. What affect does degranulation of mast cells have on the blood vessels?

Answer 9

• binds H1 receptors releasing nitric oxide

- increases vasodilation and blood vessel permeability

Question 10

In an allergic reaction there are 2 phases, acute and chronic. In the chronic phase Granulocyte-macrophage colony-stimulating factor (GM-CSF) is activated. What is the role of GM-CSF?

Answer 10

• stimulates bone marrow

- proliferation of eosinophils

Question 11

What is immune tolerance?

Answer 11

• immune systems ability to determine what is pathogenic and what is not
• we don’t want immune response if not needed, like in type I hypersensitivity

Question 12

In patients who suffer with chronic asthma and who are poorly controlled with their inhalers, what happens to the airways of these patients?

1 - re-modelling of muscle surrounding bronchi
2 - death of bronchi
3 - growth of bronchi
4 - no effect

Answer 12

1 - re-modelling of muscle surrounding bronchi

- smooth muscle and basement membrane undergo hyperplasia

Question 13

Following the acute phase of an allergic reaction, how long can it take for the late phase to begin?

1 - 2-6 minutes
2 - 2-6 hours
3 - 2-6 days
4 - 2-6 weeks

Answer 13

2 - 2-6 hours

Question 14

Physically are we able to see any symptoms in a patients affected tissue in the late phase of an allergic reaction?

1 - no all inside the body
2 - redness and swelling
3 - psoriasis develops
4 - loss of function of tissue

Answer 14

2 - redness and swelling

Question 15

In the late phase reaction which cells can be located in higher than normal concentrations at the site of allergic inflammation?

1 - eosinophils, neutrophils, macrophages, lymphocytes (CD4 T cells)
2 - eosinophils, neutrophils, mast cells, lymphocytes (CD4 T cells)
3 - eosinophils, neutrophils, mast cells and B cells
4 - macrophages, neutrophils, macrophages, lymphocytes (CD4 T cells)

Answer 15

2 - eosinophils, neutrophils, mast cells, lymphocytes (CD4 T cells)

Question 16

There are 4 main types of CD4 T helper cells (Th1, Th2, Th17 and Tregs). Which transcription factor stimulates the transformation of a CD4 T helper cell into a T1 helper cell?

1 - Foxp3
2 - GATA-3
3 - RORyt
4 - T-bet

Answer 16

4 - T-bet

- anti-viral in function

Question 17

There are 4 main types of CD4 T helper cells (Th1, Th2, Th17 and Tregs). Which transcription factor stimulates the transformation of a CD4 T helper cell into a T2 helper cell?

1 - Foxp3
2 - GATA-3
3 - RORyt
4 - T-bet

Answer 17

2 - GATA-3

• anti-parasitic
• specific transformation factor ensures body is prepared to fight parasites

Question 18

There are 4 main types of CD4 T helper cells (Th1, Th2, Th17 and Tregs). Which transcription factor stimulates the transformation of a CD4 T helper cell into a T17 helper cell?

1 - Foxp3
2 - GATA-3
3 - RORyt
4 - T-bet

Answer 18

3 - RORyt = RAR-related orphan receptor gamma

- anti-bacterial

Question 19

There are 4 main types of CD4 T helper cells (Th1, Th2, Th17 and Tregs). Which transcription factor stimulates the transformation of a CD4 T helper cell into a Treg helper cell?

1 - Foxp3
2 - GATA-3
3 - RORyt
4 - T-bet

Answer 19

1 - Foxp3

- suppression of T cells and antigen presenting cells

Question 20

There are 4 main types of CD4 T helper cells (Th1, Th2, Th17 and Tregs). Which T helper cell has been associated with the chronic response in allergies?

1 - Th1
2 - Th2
3 - Th17
4 - Tregs

Answer 20

2 - Th2, specifically the secretions from this cell

- IL-4, IL-5 and IL-13

Question 21

What % of people living with allergies have a severely debilitating form of their condition?

1 - 20%
2 - 40%
3 - 60%
4 - 80%

Answer 21

1 - 20%

- can be asthma attack, anaphylactic shock, or even death from an allergic reaction

Question 22

What % of the developed world populations have allergies?

1 - 20%
2 - 40%
3 - 60%
4 - 80%

Answer 22

1 - 20%

Question 23

Can genetics explain all allergies?

Answer 23

• no

- likely to be polygenic, but no direct cause

Question 24

The hygiene hypothesis states that the use of clean procedures limits exposure to microorganisms and antigens at an early age. This could mean that early exposure to a range of microorganisms and antigens is reduced and increases the risk of atopy. What affect does low hygiene have on:

• pathogen load
• number of T2 and T1 helper cells
• number of Treg cells

Answer 24

• pathogen load = increased
• more T1 than T2 helper T cells
• Treg cells = increased in number

Question 25

The hygiene hypothesis states that the use of clean procedures limits exposure to microorganisms and antigens at an early age. This could mean that early exposure to a range of microorganisms and antigens is reduced and increases the risk of atopy. What affect does high hygiene have on: - pathogen load - number of T2 and T1 helper cells - number of Treg cells

Answer 25

- pathogen load = decreased - more T2 than T1 helper T cells which is hypothesised why they have allergies - Treg cells = decreased in number, so no monitoring of T cells that shouldn't be activated

Question 26

What is the skin allergen test that is able to test for allergens?

Answer 26

- patient receives drops of common allergens placed on their forearm - patient then has a prick for each allergen to get allergen under the skin - patients are then left for 15 minutes to see if they have any reactions

Question 27

In the skin allergen test, if a patient is allergic to one of the allergens, what will happen to the skin where that allergen was administered?

Answer 27

- red - itchy - slightly swollen lumps

Question 28

In the skin allergen test, what is the positive control that all people should react with? 1 - pollen 2 - cat hair 3 - dog hair 4 - histamine

Answer 28

4 - histamine

Question 29

In the skin allergen test, what layer of skin is punctured? 1 - epidermis 2 - dermis 3 - subcutaneous 4 - intravenous

Answer 29

1 - epidermis | - there shouldn't be bleeding

Question 30

Allergies are normally diagnosed using an indirect ELISA. Organise the ELISA steps below used when diagnosing an allergy? - allergen of interest is used to coat bottom of the wells - colour changes and read on a plate reader - polyclonal antibody containing fluorophore is added - patients serum is added and incubated with allergen

Answer 30

``` 1st = allergen of interest is used to coat bottom of the wells 2nd = patients serum is added and incubated with allergen 3rd = polyclonal antibody containing fluorophore is added 4th = colour changes and read on a plate reader ``` wash and incubation steps occur throughout

Question 31

If a patient has an allergy and has asthma, they may begin to have an asthma attack. What treatment should these patients use to relieve their symptoms? 1 - B2 agonists (salbutamol) 2 - adrenalin 3 - anti-histamines 4 - B1 agonist

Answer 31

1 - B2 agonists (salbutamol) | - vasodilate blood vessels

Question 32

If a patient goes into anaphylactic shock due to an allergic reaction, they are generally given medication through a pen. What drug is contained within the pen? 1 - B2 agonists (salbutamol) 2 - adrenalin 3 - anti-histamines 4 - B1 agonist

Answer 32

2 - adrenalin | - called an epi pen for epinephrine, which is another name for adrenalin

Question 33

What is the core anti-histamine drug that we need to know? 1 - B2 agonists (salbutamol) 2 - adrenalin 3 - anti-histamines 4 - Chlorphenamine

Answer 33

4 - Chlorphenamine

Question 34

Chlorphenamine is the core anti-histamine drug that we need to know. What is the mechanism of action of this drug? 1 - binds anti-histamine and renders it inactive 2 - binds H1 receptors as an agonist 3 - binds H1 receptors and impairs binding of histamine 4 - binds to smooth muscle in bronchi

Answer 34

3 - binds H1 receptors and impairs binding of histamine

Question 35

What is the only core leukotriene receptor antagonist that is licensed in the UK? 1 - chlorphenamine 2 - adrenalin 3 - montelukast 4 - salbutamol

Answer 35

3 - montelukast - not as affective as H1 receptor anti-histamines - BUT more commonly used in chronic asthma

Question 36

Which glucocorticoid can be used to treat an allergy and is inhaled? 1 - Methylprednisolone 2 - Beclometasone 3 - Prednisolone 4 - Hydrocortisone

Answer 36

2 - Beclometasone

Question 37

Which glucocorticoid can be used to treat an allergy and is applied to the skin? 1 - Methylprednisolone 2 - Beclometasone 3 - Prednisolone 4 - Hydrocortisone

Answer 37

4 - Hydrocortisone

Question 38

There is a steroid medication that has equal has equal glucocorticoid and mineralocorticoid activity and can elicit the following effects: - inhibition of phospholipase A2 - inhibition of Nuclear Factor-kappa B, - inhibition of other inflammatory transcription factors - promotion of anti-inflammatory genes Which steroid medication is this? 1 - Methylprednisolone 2 - Beclometasone 3 - Prednisolone 4 - Hydrocortisone

Answer 38

4 - Hydrocortisone