HSR

Question 1

what is the series of events in order that occurs following first exposure to an allergen

Answer 1

allergen peptides are presented to the TH2 CD4 T cells—> TH2 CD4 T cells secrete IL-4 and activate B cells to become plasma cells–> IL-4 activated plasma cells secrete allergen-specific IgE—> allergen-specific IgE coats the surface of mast cells

Question 2

what happens if you block the increase in calcium

Answer 2

the production of lipid mediators will be reduced

Question 3

how does epinephrine work to restore breathing in a patient with anaphylaxis

Answer 3

activates B2 receptor

Question 4

what happens in type II HSR

Answer 4

IgG antibody targets surface antigen

Question 5

what happens in type III HSR

Answer 5

IgM binds soluble antigen

Question 6

which HSR is cell-mediated

Answer 6

type IV

Question 7

type I HSR is mediated by ___

Answer 7

IgE

Question 8

type I is _____ hypersensitivity

Answer 8

immediate

Question 9

type III is ______ mediated hypersensitivity

Answer 9

immune complex

Question 10

type II is ____ mediated hypersensitivity

Answer 10

antibody

Question 11

what happens after RE-exposure to an allergen

Answer 11

soluble antigen binds IgE on surface of mast cells and basophils–> IgE cross-linking—> degranulation and release of inflammatory mediators—> allergy symptoms

Question 12

increase in Ca channels in the membrane and release of Ca from intracellular stores in the ER causes ___

Answer 12

formation of arachidonic acid, by activating phospholipase A2

Question 13

arachidonic acid is converted to

Answer 13

prostaglandins and leukotrienes

Question 14

amplified Ca also promotes the assembly of _____ and their movement of the granules towards the plasma membranes for degranulation

Answer 14

microtubules

Question 15

blocking of Ca influx and thereby inhibiting the mast cell degranulation is the mode of action of ___

Answer 15

cromolyn (mast cell stabilizer)

Question 16

an increase in adenylate cyclase with a rapid increase in cAMP activates ___

Answer 16

cAMP-dependent processes that sensitize granule-membrane proteins to Ca, eventually causes granules to SWELL, fuse w/ the membrane, and release their contents

Question 17

what triggers degranulation by mast cells

Answer 17

the increase in intracellular Ca by both release of ER Ca and the influx of extracellular Ca following IgE binding to IgE receptors.

Question 18

drugs that persistently increase intracellular ____ such as adrenaline, terbutaline, or salbutamol stabilize the mast cell and prevent degranulation and mediator release

Answer 18

cAMP

Question 19

what are the early responding mediators

Answer 19

histamine, tryptase, kininogenase, ECF-A, leukotriene, prostaglandin

Question 20

what is histamine responsible for

Answer 20

bronchoconstriction, mucus secretion, vasodilation, vascular permeability

Question 21

what is tryptase responsible for

Answer 21

proteolysis; breakdown of proteins

Question 22

what is kininogenase responsible for

Answer 22

kinins and vasodilation, vascular permeability, edema

Question 23

what is ECF-A responsible for

Answer 23

attract eosinophils and neutrophils, release hydrolytic enzymes causing necrosis

Question 24

what is leukotriene responsible for

Answer 24

same as histamine but 1000x more potent

Question 25

what is prostaglandin responsible for

Answer 25

pain and edema thru vascular leakage

Question 26

what is a late responding mediator

Answer 26

cytokines: TNFa: for leukocyte recruitment

Question 27

what is immediate reaction caused by when allergy testing

Answer 27

IgE-,mediated degranulation of mast cells in the skin, histamine increasing the permeability of local blood vessels causing leakiness and swelling (edema)

Question 28

what is late phase reaction caused by when allergy testing

Answer 28

leukotrienes, chemokines, and cytokines released from mast cells after IgE-mediated activation

Question 29

who should consider allergy vaccinations

Answer 29

moderate to severe symptoms, year round symptoms, does not respond to medications, triggered by an allergen that is not easily avoided

Question 30

how do allergy vaccinations work

Answer 30

series of injections with increasing antigen concentration to reduce the allergen-specific IgE and increase the antigen-specific IgG4 (blocking Ab)

Question 31

type II HSR adverse drug reactions

Answer 31

penicillins (haptens), quinine

Question 32

how does penicillin cause adverse drug reaction

Answer 32

can attach to surface proteins on RBCs, elicits autoimmune IgG Abs that attach to the surface of RBCs and cause hemolysis

Question 33

how does quinine cause adverse drug reaction

Answer 33

can attach to platelets, lead to thrombocytopenia with bleeding tendency

Question 34

what is a hapten

Answer 34

chemical moiety too small to elicit a T cell response alone

Question 35

poison ivy is an example of type __ HSR

Answer 35

IV