Immunopathology 1 Flashcards
What are haptens?
Atoms or molecules that bind to a body protein, then adduct is attacked by immune system.
i.e. becoming allergic to nickel jewelry
What is the most important eosinophil attractant/activatory?
IL-5
What is a type 1 immune injury?
Inappropriate function of Th2, IgE, mast cell, eosinophil system- major defense against worms.
Allergic rxns, histamine is always present in mast cell granules. Includes urticaria
What is the first thing you should consider when you observe eosinophilic gastroenteritis?
Food allergy (IgE mediated)
What causes Goodpasture’s disease?
What type of Hypersensitivity rxn?
Ab’s against basement membrane of lungs, kidneys
Type II
What causes Acute Hemolytic Transfusion Rxns?
Ab’s in donor plasma against HLA antigens in recipient
What causes Grave’s Disease?
What type of Hypersensitivity?
IgG Ab’s against TSH receptors-> turn on receptors-> hyperthyroidism
Type II
What causes Erythroblastosis fetalis?
Ab’s against fetal (Rh+) blood cells from Rh- mom upon second pregnancy
What are the distinguishing features of Type II hypersensitivity rxn’s?
Ab against a FIXED Ag on a cell in tissue
IgG and IgM mediated
Distinguishing features of Type III hypersensitivity rxn?
Ag-Ab complex forms in circulation, deposits in tissue
IgG, IgM mediated
Distinguishing features of Type IV hypersensitivity rxn?
Delayed-type hypersensitivity reaction
T-cell mediated, no antibodies
Distinguishing features of Type 1 hypersensitivity rxn?
IgE-> mast cell degranulation
Eosinophil mediated (IL-5)- protects against worms!
Early response- histamine release
Late response- eosinophil damage mediated by leukotrienes liberated from cell membranes
What mediates anaphylaxis?
Hypersensitivity Type 1-> massive IgE mediated response
also C5a and C5b- anaphylotoxins
What is hyperacute rejection?
Bad Type III hypersensitivity reaction
Pt has Ab’s against donor organ-> turns white, bloodless
