BLD section 6 quiz Flashcards
(80 cards)
Type 1 hypersensitivity
IgE mediated, typically environmental allergens
Type 2 hypersensitivity
IgG, antibody cell mediated causes cytotoxicity, complement activation, drug response creates novel antigen, which causes hypersensitive response at next exposure
Type 3 hypersensitivity
IgG, immune complex mediated, complement activation, Immune complex activating complement which acts in an autoimmune fashion
Type 4 hypersensitivity
Cell mediated, sensitized T cells (typically cytotoxic, can be Th1), activated macrophages, Contact dermatitis, bacterial infection IgE
How does immediate hypersensitivity differ from delayed type hypersensitivity
Immediate hypersensitivity is type 1 while delayed is type 4 and usually 1-3 days after exposure
What type of hypersensitivity is associated with histamine release
type 1
Describe the utility of total serum IgE testing
RIST. Elevated total serum IgE
What are advantages to total serum IgE testing
inexpensive and suggests further testing
What are disadvantages to total serum IgE testing
not sensitive and doesn’t identify allergen
Describe the utility of skin prick testing
wheal reaction
What are advantages to skin prick testing
positive test is clinically significant
What are disadvantages to skin prick testing
danger of systemic reaction, traumatic to the patient, and only tests limited individual allergens
Describe the utility of allergen specific testing
RAST
What are advantages to allergen specific testing
can be taken with antihistamines and only require single skin puncture to draw blood for serum testing
What are disadvantages to allergen specific testing
lower specificity than skin testing and only tells if IgE is present not if its responsible for current allergic symptoms
Identify common examples of type II hypersensitivities
Hemolytic anemia and hemolytic disease of fetus and newborn (HDFN)
Identify the type of hypersensitivity for: Serum sickness
Type 3
Identify the type of hypersensitivity for: Celiac disease
Type 4
Identify the type of hypersensitivity for: Poison ivy
Type 4
Identify the type of hypersensitivity for: Allergic asthma
Type 1
Identify the type of hypersensitivity for: Food allergies
Type 1
Identify which hypersensitivity responses involve complement activation
Type 2 and type 3 hypersensitivity involves complement activation
Identify whether CD4+ T cells, CD8+ T cells, and/or B cells are responsible for autoimmune disease
Both autoimmune antibodies and Tc have been found to be responsible for eliciting autoimmunity - usually one or the other cell type dominates
Identify two proteins involved in T lymphocyte self-tolerance that when defective in humans lead to generalized autoimmune disease
Homozygous deletion mutations of AIRE (autoimmune response element) or FoxP3 cause generalized autoimmunity
-AIRE - produces proteins for negative selection
- FoxP3 - a transcription factor that maintains Treg phenotype