Hypersensitivity Flashcards
What is hypersensitivity?
An exaggerated or inappropriate immune response to an antigen that leads to discomfort, tissue damage, and disease.
How many types of hypersensitivity?
4
Hypersensitivity timelines.
- minutes to hours
- hours to days
- hours to days
- 48-72 hours
Type III name and examples?
Immune Complex mediated hypersensitivity
Arthus reaction
Serum sickness
Systemic lupus erythematosus
Glomerulonephritis
Type I name and examples?
anaphylactic hypersensitivity
Allergic rxn, sweet itch
Type IV name and examples?
Delayed Type
Contact dermatitis
Tuberculin reaction
Type II name and examples?
Cytotoxic hypersensitivity
Hemolytic anemia, myasthenia gravis, Grave’s disease
Draw out type of hypersensitivity reactions on slide 5.
3 components of Type I Hypersensitivity?
Mast cell, eosinophil, IgE
Write out characteristics of Mast cell and eosinophil.
Slide 6
What are allergies?
Reaction of body to allergens that is detrimental to the host
Discuss examples of allergens.
Slide 7
2 steps of allergic reactions?
sensitization - usually mild (first exposure)
Subsequent exposure (may get serious)
Predisposition of allergies?
Yes, usually genetic
Draw out allergen –> allergic responses mechanism.
Slide 8
Draw out steps of mast cell degranulation.
Slide 9
Draw out Slide 10.
What is anaphylaxis?
What can histamines cause?
sudden shock syndrome resulting from the massive release of mast cell mediators
Major smooth muscle contraction THUS leading to airway closing
Draw out pathway of sweet itch. Slide 11.
Describe self-antigens of type II.
Slide 14
Three factors of anaphylaxis?
type of antigen, amount of IgE produced and the route of exposure
Where does Type II hypersensitivity occur?
cytotoxic
Describe extrinsic antigens of type II.
Slide 14
Describe cross reactive antibodies of type II.
Slide 14
What complex becomes the target of complement system which results in cytotoxicity.
ag-ab complex
How does the antigen-antibody complex result in cytotoxicity?
Slide 15
Pathway of penicillin? Slide 16
When is the ag-ab complex beneficial?
Detrimental? Slide 17 and 18
When will no immune response happen in blood transfusions?
If the donor RBC are identical to those of the recipient
When do transfusion reactions most often occur?
if the recipient has alloantibodies that bind the donor’s RBC
How does the recipient acquire alloantibodies?
-pre-existing in the body
-developed antibodies from previous transfusions
-sometimes the donor has antibodies that they pass on
Describe how blood matching works.
Slide 20
Review Blood group system.
Slide 21
What happens when an individual with blood group A receives blood from a donor that has blood group B.
Write out steps. Slide 22.
Hemolytic anemia
Induces death of donor RBCs
Discuss the mechanism and result of neonatal isoerythrolysis in foals.
Slide 23
Describe Bovine neonatal pancytopenia.
Slide 24
Discuss the different zones and sizes of complexes of type III.
Slide 29
What is Grave’s disease?
autoantibodies against the TSH receptor cause overproduction of thyroid hormones
Draw out image of non-cytotoxic type II hypersensitivity.
Slide 25
Discuss Type III hypersensitivity.
Slide 28
Draw out pathway of type III hypersensitivity.
Slide 30
Discuss the features of local type III hypersensitivity (Arthus Reaction)
Slide 31
Discuss systemic type III hypersensitivity.
Slide 32
Discuss the different types of immune complexes in the blood.
Slide 33
Discuss what happens when the complex system fails in regards to complement receptors and phagocytes.
Slide 34
Draw out pathways of immune complexes in blood.
Slide 35
Discuss the features of MPGN.
Type locations?
Slide 36
What does C3 deficiency result in?
glumerulonephritis
Glomerulonephritis lesions are ___________ instead of inflammatory.
proliferative
What is IMPA?
Result?
Immune complexes deposit in synovial fluid
Neutrophilic inflammation in the joints
Describe serum sickness of type III hypersensitivity.
Slide 40
Describe systemic lupus erythematosus.
Slide 41.
What are type IV hypersensitivity reactions caused by?
T cell response to complexes of MHC class II and peptide antigens derived from foreign proteins or from chemically modified proteins
Describe a tuberculin reaction.
Slide 43.
Draw out pathway of type IV hypersensitivity.
Slide 44
Draw out pathway of allergic contact dermatitis (type IV).
Slide 45
