Immune System Gone Wrong: Part 1

Question 1

Type I hypersensitivity reaction is mediated by..

Answer 1

IgE antibodies

Question 2

Type II hypersensitivity reaction is mediated by…

Answer 2

IgG or IgM antibodies

Question 3

Is a Type II hypersensitivity reaction cytotoxic?

Answer 3

Yes

Question 4

Type III hypersensitivity reaction is mediated by…

Answer 4

Immune complexes

Question 5

Type IV hypersensitivity reactions are mediated by…

Answer 5

Cellular response

Question 6

Are Type IV reactions immediate or delayed?

Answer 6

Delayed

Question 7

What is the acronym to remember the four different types of sensitivity reactions?

Answer 7

ACID

Question 8

What are the two stages that hypersensitivity reactions go through?

Answer 8

• Sensitization stage
• Effector stage

Question 9

When does the sensitivity stage occur?

Answer 9

During the first exposure an individual has to an antigen

Question 10

What happens during the sensitization stage for Type I hypersensitivity reactions?

Answer 10

Mast cells and basophils become sensitized to the allergen

Question 11

What happens during the sensitization stage for Type II hypersensitivity reactions?

Answer 11

Production of antibodies to recognize substances

Question 12

What happens during the sensitization stage for Type III hypersensitivity reactions?

Answer 12

Presence of antibodies against the offending antigen in the serum of affected individuals

Question 13

What happens during the sensitization stage for Type IV hypersensitivity reactions?

Answer 13

T cells are sensitized and memory T cells are produced, 7-10 days later

Question 14

What is the effector stage?

Answer 14

Second or subsequent exposure to the antigen

Question 15

What stage causes damage to the host?

Answer 15

Effector/secondary immune response

Question 16

What type of hypersensitivity starts immediate allergic reaction?

Answer 16

Type I

Question 17

What type of hypersensitivity uses Th2?

Answer 17

Type I

Question 18

What is atopy?

Answer 18

Hereditary predisposition to the development of immediate hypersensitivity reactions

Question 19

Atopy tends to produce what antibody in excess to extremely small amounts of naturally occurring allergens?

Answer 19

IgE

Question 20

Atopic individuals have abnormally high levels of what type of immune cell?

Answer 20

Eosinophils

Question 21

What individuals are more susceptible to allergies such as hay fever, eczema, and asthma?

Answer 21

Atopy individuals

Question 22

What is localized IgE-mediated hypersensitivity?

Answer 22

Affects a specific target tissue

Question 23

What are three examples of localized IgE mediated hypersensitivity?

Answer 23

• Asthma
• Eczema
• Hay fever

Question 24

What are three examples of systemic IgE mediated hypersensitivity?

Answer 24

• Venom
• Drugs
• Food

Question 25

What is systemic IgE-mediated hypersensitivity?

Answer 25

- Affects the whole body - Anaphylaxis

Question 26

When can an allergen crosslink the IgE molecules bound on a mast cell?

Answer 26

During subsequent exposure

Question 27

What tells mast cells to degranulate?

Answer 27

Clustering of IgE receptors

Question 28

What is released from mast cells and basophils?

Answer 28

Histamine

Question 29

What does histamine do?

Answer 29

Vasodilate blood vessels

Question 30

What cell plays a large role in chronic allergic reactions?

Answer 30

Eosinophils

Question 31

What can lead to mast and basophil cell degranulation?

Answer 31

Crosslinking of IgE antibodies

Question 32

What does a non-allergic person do?

Answer 32

Does not response to antigen or eliminates allergen with IgG, IgM, or IgA

Question 33

What is the hygiene hypothesis?

Answer 33

Children who are exposed to bacteria are less prone to developing allergies

Question 34

How is Treg cells involved in suppressing allergic reactions?

Answer 34

- Block mast cell activation - Block interleukin production - Block B cells from making IgE - Release pre-formed anaphylactic mediators

Question 35

What are the two types of treatments for allergies?

Answer 35

- Glucocorticoid steroids - Specific immunotherapy

Question 36

How do glucocorticoid steroids decrease allergy symptoms?

Answer 36

Block cytokine production of helper T cells, fewer B cells are activated

Question 37

Are glucocorticoid steroids specific for treating allergies?

Answer 37

No

Question 38

What is the only cure to allergies that has been successful?

Answer 38

Specific immunotherapy/allergy shots

Question 39

What is specific immunotherapy/allergy shots?

Answer 39

Injection of gradually increasing dose of crude extractions of allergen until a maintenance dose is achieved

Question 40

What is the immediate result of specific immunotherapy/allergy shots?

Answer 40

Mast cells become more difficult to activate in response to IgE binding

Question 41

Overtime, was does specific immunotherapy/allergy shots encourage?

Answer 41

Allergen specific B cells to switch their antibody class from IgE to another class