Immune Hypersensitivities Flashcards
Immune hypersensitivity is defined as…
Tissue damage due to an immune mechanism
Which hypersensitivity is involved with allergic reactions?
Type 1
Uses IgE, mast cells and eosinophils
Which hypersensitivity reaction is due to antibody binding to cell surface proteins?
Type 2
Which hypersensitivity reaction involves the immune complex desposition in tissue with compliment activation of inflammation?
Type 3
Which hypersensitivity reaction involves T cells ingested or mediated tissue damage?
Type 4
What are the three phases of mechanism of type 1 (atopy)?
Sensitization
Immediate Reaction
Late-Phase response
What is the basic process of a type 1 hypersensitivity reaction?
Allergen protein enters the body, TH2 cells are stimulated to get IgE cells which goes to the mast cells to release cytokines to call the eosinophils to do damage
What is sensitization in type 1?
The initial exposure to the allergic producing IgE
What happens in the immediate reaction in type 1?
Mast cell degranulation
What happens in the late-phase response in type 1?
Late reaction hours later by cytokines
What are the clinical manifestations of type 1?
Allergic rhinitis, sinusitis
Food allergies
Bronchial asthma
Anaphylaxis
What stimulates mast cell activation and degranulation?
Antigen cross-linked IgE/FcER
When an allergen is taken by the IgE to the Fc recepor, what pathways may occur?
Degranulation
Secreted cytokines
Membrane phospholipids
The granules that are released from the mast cell contain;
Histamine
Proteases
Chemotactic factor (ECF, NCF)
The membrane phospholipids make;
Arachidonic acid and PAF