Hypersensitivity

Question 1

Excessive reaction to antigenic stimulus

Answer 1

Hypersensitivity

Question 2

Immediate reaction lang ang meron sa Type I hypersensitivity. True or False?

Answer 2

False. May late phase din, 2-24 h later. May last for several days.

Question 3

Individuals who have been previously exposed to an antigen may trigger a pathologic reaction when exposed to the same antigen. T or F?

Answer 3

T. This is called sensitization

Question 4

Eosinophils are recruited to infection site by ___

Answer 4

Chemokines

Question 5

Two proteins liberated by eosinophils

Answer 5

Basic protein

Cationic protein

Question 6

Eosinophils direct which immune cells to release mediators?

Answer 6

Mast cells

Question 7

Mast cells are activated by what cross linking?

Answer 7

Cross linking of high affinity IgE-FC receptors

Question 8

Which complement proteins are involved in the activation of mast cells?

Answer 8

C5a, C3a

Question 9

Mast cells have these kind of preformed mediators, except

a. vasoactive amines
b. proteoglycans
c. enzymes
d. leukotrienes

Answer 9

D

Leukotrienes are lipid mediators that are synthesized by sequential reactions in the mast cell membranes

Question 10

Phospholipase A2 is an enzyme that an enzyme that acts on membrane
phospholipids to yield ___

Answer 10

arachidonic acid

Question 11

What is atopy?

Answer 11

predisposition to develop localized immediate

hypersensitivity reactions

Question 12

In atopy, there is higher serum IgE levels and more ___producing TH2 cells

Answer 12

IL-4

Question 13

Non-atopic allergy is triggered by __

Answer 13

triggered by temperature extremes and exercise

Question 14

Which is not consistent with the Hygiene Hypothesis?A.decreasing incidence of immediate hypersensitivity
diseases in developed countries
B.appears to be related to a decrease in infections during
early life
C.immune system is rest such that TH2 responses develop
more readily against common environmental antigens

Answer 14

A

Question 15

What kind of hypersensitivity are transfusion reactions?

Answer 15

II

Question 16

What is Erythroblastosis Fatalis?

Answer 16

there is antigenic difference between the mother
and the fetus, and IgG antibodies from the mother
cross the placenta and cause destruction of fetal
red cells

Question 17

Differentiate Type II from Type III hypersensitivity

Answer 17

Type II is mediated by antibodies AGAINST antigens

Type III is mediated by antigen-antibody complexes

Question 18

What are the phases of systemic disease for Type III hypersensitivity?

Answer 18

formation of immune complexes
deposition of immune complexes
injury caused by immune complexes

Question 19

Which is true about deposition of immune complexes?
A.Deposition is greatest with
medium sized complexes.
B.Deposition is great in glomerulus.
C.Deposition is great in synovium.
D.All are true.

Answer 19

D

Question 20

False about Arthus reaction
A.Localized area of tissue necrosis resulting from
acute immune complex vasculitis
B.As the antigen diffuses into the vascular wall, it
binds the preformed antibody, and large complexes
are formed locally
C.These complexes precipitate in the vessel walls and
cause caseous necrosis, and superimposed
thrombosis worsens the injury

Answer 20

C

Fibrinoid, not caseous