Hypersensitivities

Question 1

What are common sources of allergens?

Answer 1

inhaled materials, injected materials, ingested materials

Question 2

What is a hypersensitivity reaction?

Answer 2

undesirable reactions produced by the normal immune system, including allergies and autoimmunity

Question 3

Hypersensitivity requires a ___________ state of the host.

Answer 3

pre-sensitized (immune)

Question 4

Clinical timing of Type I, II, III, and IV hypersensitivity?

Answer 4

I - within minutes if prior sensitized

II & III- within hours if prior sensitized

IV- 2-3 days if prior sensitized, delayed

Question 5

What cells are involved in Type I hypersensitivity?

Answer 5

Mast cells
Basophils
Eosinophils

Question 6

What cells are involved in Type III hypersensitivity?

Answer 6

Neutrophils (some mast cells too)

Question 7

What cells are involved in Type IV hypersensitivity?

Answer 7

Th1, CTLs, macrophages

Question 8

What Ig classes are involved in Type I hypersensitivity?

Answer 8

IgE

Question 9

What Ig classes are involved in Type II hypersensitivity?

Answer 9

IgG, IgM

Question 10

What Ig classes are involved in Type III hypersensitivity?

Answer 10

IgG, IgA

Question 11

What Ig classes are involved in Type IV hypersensitivity?

Answer 11

none

Question 12

Clinical syndrome involved with hypersensitivity type I?

Answer 12

allergies
asthma
anaphylaxis

Question 13

Clinical syndrome involved with hypersensitivity type II?

Answer 13

Cytolysis of antibody coated cells leads to anemia, thrombocytopenia, or neutropenia

Question 14

Clinical syndrome involved with hypersensitivity type III?

Answer 14

Immune complex deposits on capillaries, complement activation leads to immune complex disease (vasculitis, glomerulonephritis, arthritis)

Question 15

Clinical syndrome involved with hypersensitivity type IV?

Answer 15

granulomas or cellular apoptosis induced by CD8 cells

Question 16

How is disease caused in Type I hypersensitivity?

Answer 16

By inflammatory molecules releases from mast cells.

Mediated by IgE attached to Mast Cells.

Question 17

Clinical signs of allergic disease are independent of the allergens entry route. True or false?

Answer 17

False

Question 18

What causes allergic anaphylaxis? How does this affect smooth muscle?

Answer 18

Inflammatory molecules released by mast cells

Animals may die due to contraction of critical smooth muscle (those lining the bronchi)

Question 19

What are the two purposes of Type I Hypersensitivity?

Answer 19

Self eliminate / self cure round worms in the gut

Eliminate allergen (antigen) from muco-cutaneous surfaces.

Question 20

What are the clinical signs of the body trying to eliminate allergens from muco-cutaneous surfaces?

Answer 20

Mucus formation, runny nose, sneezing, itching, coughing, vomiting, diarrhea

Question 21

What are the consequences of the body trying to eliminate allergens from muco-cutaneous surfaces?

Answer 21

smooth muscle contraction - bronchoconstriction

vascular permeability - edema formation

IgE microgram quantities in the blood and shortest half-life

Question 22

What are the mechanisms of tissue injury and disease in Type I?

Answer 22

mast cell derived mediators

cytokine-mediated inflammation

Question 23

What are the effector cells for Type I?

Answer 23

mast cells, basophils, eosinophils