Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
15 Cards in this Set
- Front
- Back
|
Four Hypersensitivity Reactions
|
Type I-Immediate Hypersensitivy=Allergy
Type II-involves IgG anitbody Type III-Immune complex hypersensitivty Type IV-Delayed type hypersensity (DTH)-cell-mediated hypersenitivity |
|
|
hypersensitivity reaction
|
excessive immune respone that causes damage
|
|
|
Allergy
|
Type I HS; certain diseases in which immune responeses to environmental anitgens cause tissue inflammation and oragan disfunction
|
|
|
Allergen
|
an antigen that induces allergic reaction
|
|
|
Atopy
|
allegy mediated by IgE antiboddy...pateints with this are "atopic"
|
|
|
When do type I reactions occur?
|
Within minutes to hours after the 2ND exposure to allergen
|
|
|
How are type I reactions initiated?
|
when allergen binds to IgE on the surface of mast cells, which causes degranulation with release of bioactive substances (histamine)
|
|
|
Is the etiology for an atopic agent known?
|
No, but allegries run in families (genetic factor)
|
|
|
Distinguishing feature of IgE antibody
|
binds to high affinity FCRI region on mast cells and basophils and exists only as a monomer
|
|
|
Two names for allergic rhinitis
|
allergic rhinoconjunctiivits and hay fever
|
|
|
What is the most coomon clincal expression of allergic rhinitis?
|
Its the main cuase of atopic hypersensitivity
|
|
|
What will a lab finding of allergic rhinitis consist of ?
|
Numerous eosinophils in nasal secretions and in blood AND elevated IgE
|
|
|
What are two ways to idenitfy the specific allergen to help diagnosis of allergic rhinitis?
|
Skin testing (wheal and flare responese for Type I HS) or In vitro tests
|
|
|
What's the difference b/n early and late phase reaction?
|
Early phase (immediate)-involves vasoactive amines and lipid mediators and happens right after exposure to allergen; late phase involves cytokines 2-4 hrs after exposure to allergen
|
|
|
What's the steps leading up to when mast cell release their activators?
|
1. first exposure to anitgen
2. ant. activation of TH2 cells and stimulation of IgE withcing in B cells 3. prodcution of IgE $. Binding of IgE to FcRI on mast cells 5. 2nd exposure to allergen 6. mast cells activated! |
