Hypersensitivity Rxns Flashcards
___ is characterized by overtly excessive immune response to an antigen in a sensitized individual
Hypersensitivity rxn
excessive immune response to an antigen by a sensitized individuals:
allergy
Hypersensitivity that involves IgE and is a rapid allergic rxn?
Type I
First exposure vs 2nd exposure in type I hypersensitivity?
1st: produces IgE –> causes sensitization
2nd: IgE cross-linking–>degranulation
What is a genetic predisposition to form IgE allergic rxns?
atopy
life-threatening type I rxn mediated by histamine and can be tx w/ epi?
anaphylaxis
___ regulates the development of mast cells
Factor C-kit ligand
Which hypersensitivity results from IgG and IgM and activates ADCC, classical complement, and phagocytosis?
Type II
Examples of type II:
- hemolytic transfusion and diseases (newborn)
- goodpasture’s syndrome
- other auto-immune diseases
Hypersensitivity that results from immune complex depositions that trigger inflammation and destruction of vessels?
Type III
Examples of type III:
- vasculitis
- glomerulonephritis
- serum sickness
What results from deposition of immune complexes in BVs and may be caused by certain drugs. Sx include fever, LAD, serpiginous rash, and cyclical urticarial plaques?
Serum sickness
Which hypersensitivity rxn results from CMI and is delayed?
Type IV
Development process of Type IV:
CD4+ T cells travel to infxn site–> interact w/ antigen via APC
Initial exposure in type IV:
T cells get sensitized
