Immuno 11: Hypersensitivity Flashcards
Type 1 hypersensitivity
allergy caused by IgE mast cell activation
Type 2 hypersensitivity
Antibodies directed against cells or tissues, impairing function
Type 3 hypersensitivity
Antibodies against soluble antigens form complexes and deposit in blood vessels, causing inflamation and tissue injury
Type 4 hypersensitivity
T lymphocytes specific for self antigens attack tissues
Atopy
synonym for allergy
Sequence of events in development of immediate hypersensitivity reactions
Activation of Th2/IL-4helper t cells in response to antigen
Production of IgE by Th2/IL-4
IgE binds to mast cells leading to activation
Late-phase reaction
Part of mast cell activation. Comes from neutrophil and eosinophil recruitment. Repeated bouts can cause tissue injury
IL-4 secreted by ____ stimulates _____ to switch to IgE producing plasma cells
IL-4 secreted by Tfh cells stimulates B lymphocytes to switch to IgE producing plasma cells
Histamine function
Increased vascular permeability, vasodilation, contraction of smooth muscle
Arachidonic acid metabolites are released by
Mast cells
Arachidonic acid metabolites include
Prostaglandins and leukotrienes
Proteases released by mast cells cause
Tissue damage
Cytokines produced by mast cells stimulate the recruitment of_______, which cause the _________.
Cytokines produced by mast cells stimulate the recruitment of leukocytes, which cause the late-phase reaction.
Hay fever
Allergic rhinitis and sinusitis caused by pollen
Most common cause of asthma
Respiratory allergy in which inhaled allergens stimulate bronchial mast cells to release mediators like leukotrines which cause bronchial constriction