Hyper Sensitivity Reactions

Question 1

4 types of hyper sensitivity

Answer 1

Type 1 - allergy and anaphylaxis
Type 2 - antibody mediate cytotoxcity
Type 3 - immune complex disease
Type 4 - delayed type

Question 2

Allergy and Anaphylaxis (type 1)

Answer 2

rapidly progressing immune reaction through antigen binding to surface of IgE coated basophils or mast cells

Question 3

Allergy

Answer 3

localized

Question 4

Anaphylaxis

Answer 4

systemic

Question 5

Atopy

Answer 5

increased tendency to develop allergies. They make IgE in response to allergens even though that’s normally just for parasites

Question 6

Th2 response

Answer 6

absence of inflammation

Question 7

Hygiene hypothesis

Answer 7

Growing up in really clean environments decreases Th2 mediated immunity and increased IgE

Question 8

Basophil

Answer 8

similiar to mast cell but exist in bloodstream not the tissue
non phagocytic
granulated
have a lot of histamine

Question 9

What happens during 1st exposure to allergen

Answer 9

increased IgE, no anaphylaxis (that can take multiple exposures)

Question 10

What happens during later exposures to allergen

Answer 10

IgE binds to Fc receptors on basophils and mast cells

allergen binds to surface-bound IgE, causing cells to release granule contents

Question 11

What are symptoms of anaphylaxis

Answer 11

first symptom is usually tightness in chest
get edema and smooth muscle contraction. You can die because of how much it messes with your lungs. Starts very quickly as well

Question 12

Leuotrines

Answer 12

have similar effect as histamine but must be synthesized. Has a longer effect.

Question 13

Eosinophils

Answer 13

anti parasitic, especially for helminths
accumulate in nasal and bronchial mucosa in respiratory allergies and intestinal mucosa during worm infestation
attach to worms and release granules containing hydrolytic enzymes

Question 14

Late phase response of anaphylaxis

Answer 14

develop 6-8 hours after immediate reaction
2nd phase of smooth muscle contraction
sustained edema
recruitment of eosinophils and Th2 cells
remodeling of tissue
can lead to chronic asthma and associated airway hyperreactivity

Question 15

What is the only treatment that reverses anaphylaxis

Answer 15

epinephrine

Question 16

Grave’s Disease

Answer 16

antibodies to TSH receptor causes overproduction of thyroid hormones causing hyperthyroidism

Question 17

Myasthenia gravis

Answer 17

antibodies to acetylcholine receptor blocks nerve impulse transmission to muscles

Question 18

Hemolytic disease of newborn

Answer 18

Rh- mom
Rh + fetus

Remember this has no effect on the first child, but subsequent Rh+ fetuses will be affected

Question 19

What can Immune Complex Disease (type 3) be induced by?

Answer 19

autoimmune disease
serum sickness
drug reactions
infectious disease
inhaled allergens

Question 20

Pathogensis of immune complex disease

Answer 20

immune complex lodge in tissue
activate complement (C5a) and get neutrophil accumulation
lysosomal enzymes damage tissue, cause fever, urticaria, arthritis, lymph node enlargement, proteinuria

Question 21

Serum sickness

Answer 21

caused by repeat injection of foreign serum

Question 22

What is supposed to happen to immune complexes

Answer 22

get rapidly removed

Question 23

Delayed type hypersensitivity (DTH) (Type IV)

Answer 23

24-72 hours after exposure
cell-mediated immune response.
Mediated by TH1
is a memory response

Question 24

Contact Dermatitis

Answer 24

small molecules complexed w/ skin protein presenting on antigen-presenting cells to T helper cells
CD4+ and CD8+ secrete inflammatory cytokines, including IFN-gamma

Question 25

Do AIDS patients that get infected with TB develop granulomas?

Answer 25

no