TYPE I ANAPHYLACTIC HYPERSENSITIVITY REACTION Flashcards
what are the two phases?
immediate
late
which phase is this?
preformed mediators vasodilation vascular leakage smooth muscle contraction mast cells rapid, like 5-30 minutes after antigen exposure
immediate
which phase is this?
mediators formed de novo inflammation tissue destruction eosinophils 2-8 hours later lasts for days intense
late
what is the sequence of events?
activation of TH2 cells and production of IgE TH2 cells induced -IL4 -IL5 -IL13
IgE antibodies are the primary mediator binding to mast cells
mast cells have this very important high affinity receptor?
FcER1
what are the primary mediators?
vasoactive amines -histamine -adenosine chemotactic factors -neutrophils -eosinophils neutral proteases -tryptase
what are the secondary mediators?
PGD2
LTC4 and LTD4
LTB4
name this secondary mediators?
most abundant mediator generated by cyclo oxygenase pathway
- bronchospasm
- mucus secretion
PGD2
name this secondary mediators?
most potent vasoactive and spasmogenic agents
-more active than histamine
LTC4 and LTD4
name this secondary mediators?
highly chemotactic for neutrophils, eosinophils, and monocytes
LTB4
what are the important cytokines?
TNF
chemokines
IL4 and IL5
IL13
what are the two reactions that can occur as a result of this?
systemic
local
name this reaction?
bee venom, drugs/medications
parenteral or oral administration of allergen
greater the exposure, greater the reaction
pruritis, urticaria, erythema
bronchoconstriction, laryngeal edema, obstruction
systemic reaction
name this reaction?
limited exposure
skin, GI, lung
atopic allergy (genetic predisposition)
urticaria, allergic rhinitis, asthma
local reaction
