Hypersensitivity and Autoimmunity Flashcards
Define hypersensitivity.
A group of disorders in which the normally beneficial components of the immune response act in an exaggerated or inappropriate fashion to environmental antigens which don’t usually cause the tissue damage.
What is responsible for the tissue damage?
Exaggerated immune response.
What are hypersensitivity types 1, 2 and 3 mediated via?
Antibodies.
What cause type 4 hypersensitivity?
Inappropriate actions of T helper 1 cells
What is the other name for type 1 hypersensitivity?
Allergy
What is type 1 hypersensitivity caused by?
Inappropriate synthesis of IgE.
In what 4 ways can a type 1 hypersensitivity reaction be started?
Ingestion
Inhalation
Injection
Skin contact
What are allergens?
Antigens which cause IgE production.
What are the 5 factors of immunity? RIREC
Recognition Interaction Response Elimination Control and Regulation
What allows IgE to bind to Fc receptors?
It has an extra peptide sequences to other immunoglobulins.
Where are Fc receptors found?
On the surface of mast cells.
What do T helper cells do?
Aid B-cells in producing IgE
What are the 3 types of Th1 cells?
IL-2
Gamma - IFN
TNF
What are the 4 types of Th2 cells?
IL- 4
IL - 6
IL - 10
IL - 13
Define atopy.
A genetic tendency to produce IgE to normally innocuous, common environmental allergens.
Define allergy.
A clinical expression of the atopic tendency.
What % of the population suffers from allergy?
15-20%.
What are 3 specific triggers of IgE?
Insect venom Pollen Mould spores Animal dander Food allergens
What are 3 nonspecific triggers of IgE?
Exercise Tobacco Pollution SO2 Water Food items
What are the 5 symptoms of allergy and atopy?
Anaphylaxis Asthma Rhinitis and Conjunctivitis Urticaria Gastrointestinal