EXAM 4 Hypersensitivity, Allergy, and Chronic Inflammation Flashcards
___ causes self harm during hypersensitivity reactions
immunity
who discovered anaphylaxis?
paul portier and charles richet
- looked at proteins associated with portugese man o’ war toxin
- repeated exposure rapidly killed dogs
- vomiting, diarrhea, asphyxia
what is anaphylaxis?
- a severe, immediate, and system-wide harmful immune response to a non-pathogenic antigen
- first identified hypersensitivity reaction
what is a hypersensitivity reaction?
an immediate or delayed immune response to innocuous antigens (often, but not always) resulting in healthy tissue damage
what are the 4 types of hypersensitivity reactions? what are they defined by?
they are defined by their effector mechanisms

which hypersensitivity reactions are humorally mediated?
types I, II, and III
which hypersensitivity reaction is cell-mediated?
type IV
allergy is a type ___ hypersensitivity reaction
I
what is an allergen?
- non-pathogenic antigens that illicit hypersensitivity reactions
- proteins or glycoproteins
- enzymatic activity, often proteases
- interact with PRRs
- low, persistent concentrations at mucosal surfaces
which 3 granulocytes are allergen-IgE activated (type I hypersensitivity reaction)?
mast cells, basophils, eosinophils
type I hypersensitivity reactions are mediated by what immunoglobulin?
IgE
is a type I hypersensitivity reaction immedate or delayed?
immediate
what are some examples of how type I hypersensitivity reactions are localized?
allergic rhinitis (hayfever), allergic asthma, eczema, food allergies
what is an example of how type I hypersensitivity reactions can be systemic?
anaphylactic shock
are type I hypersensitivity reactions local or systemic?
they can be both
what is the type I hypersensitivity reaction?
- antigen induces cross-linking of IgE bound to mast cells and basophils with release of vasoactive mediators
- typical manifestations - includes systemic anaphylaxis and localized anaphylaxis such as hay fever, asthma, hives, food allergies, and eczema

granulocytes are ___ effectors in parasite immunity
Th2
mast cell degranulation drives ___
inflammation
describe mast-cell activation and degranulation in the GI tract
- increased fluid secretion, increased peristalsis
- expulsion of GI tract contents by diarrhea and/or vomiting
describe mast-cell activation and degranulation in the airways
- decreased diameter, increased mucus secretion
- expulsion of airway contents through coughing, sneezing, and expulsion of phlegm
describe mast-cell activation and degranulation in the blood vessels
- increased blood flow, increased permeability
- edema and inflammation, increased flow of antigens in lymph to lymph nodes