IMMUNOLOGY FINAL |THE SMART WAY TO PASS | REAL
TESTS, REAL RESULTS!
the challenge to the immune system Answer: tolerate self molecules
tolerate harmless non self molecules
respond to dangerous non self molecules
sometime the immune system fails the challange and we generate Answer: adaptive response to
a harmless non self molecule
response to reexposure Answer: hypersensitivity
allergic reaction
allergen Answer: molecules that cause allergy
aka atopy
incidence of allergy has been Answer: increasing the last 30-40 years
in industrialized countries
non industrialized countries allergy is relatively unusual phenomenon
early childhood exposure to Answer: helminths
important for normal development of the immune system
industrialized parts of the world Answer: are no longer exposed to helminth infections
reason for high incidence of allergy and autoimmunity in the west
common allergens Answer: inhaled materials (plant pollen, dust mite feces)
injected materials (insect venom, drugs)
ingested materials ( peanuts, shellfish)
contacted materials (plant oil, metal)
four types of allergic/ hypersensitivity reactions Answer: type I -IV
type I Answer: antibody mediated
allergen binds to IgE on mast cell, basophils and eosinophils
cells explosively and rapidly degranulate releasing proinflammitory mediators
pollen allergy- anaphylactic shock
type II Answer: antibody mediated
small molecule binds and modifies host cell
APPHIA – Crafted with Care and Precision for Academic Excellence.
1
, B cell IgG responds to modified component on host cell
complement activation and phagocytosis causes inflammation and tissue damage
penicillin
Type III Answer: antibody mediated
antibodies respond to soluble proteins
immune complexs deposit on the walls of small blood vessels and lung tissue
inflammation
diabetics - bovine insulin and therapeutic monoclonal antibodies
type IV Answer: T cell mediated
Th1 or CD8 responds to modified proteins
response takes a few days to develop
poison ivy/ metal allergies
Type I hypersensitivity is driven by Answer: IgE driven degranulation
important defense again helminths
large size of parasitic worms makes them resistant to Answer: direct killing by CTL,
macrophages, and antibodies
mast cell degranulation Answer: immune system is directed at stimulating physiological and
behavioral mechanisms involved in expulsion from the body (diarrhea, sneezing vomiting,
scratching eat)
Type I hypersensitivity is promoted by Answer: Th2 responses
IL-4 is important isotype switching factor for IgE
IL-5 is important factor for increasing eosinophil production from bone marrow
Type I hypersensitivity degranulation is triggered by Answer: harmless antigens (allergens)
Ige and FcER1 Answer: binding of mast cells
IgE is mostly present bound to Answer: FcER1
high affinity
on mast cell in tissues
IgE is held in Answer: a rigid "shrimp" like structure through CE2 domains
CE2 domains Answer: unique to IgE
no hinge regions
APPHIA – Crafted with Care and Precision for Academic Excellence.
2
TESTS, REAL RESULTS!
the challenge to the immune system Answer: tolerate self molecules
tolerate harmless non self molecules
respond to dangerous non self molecules
sometime the immune system fails the challange and we generate Answer: adaptive response to
a harmless non self molecule
response to reexposure Answer: hypersensitivity
allergic reaction
allergen Answer: molecules that cause allergy
aka atopy
incidence of allergy has been Answer: increasing the last 30-40 years
in industrialized countries
non industrialized countries allergy is relatively unusual phenomenon
early childhood exposure to Answer: helminths
important for normal development of the immune system
industrialized parts of the world Answer: are no longer exposed to helminth infections
reason for high incidence of allergy and autoimmunity in the west
common allergens Answer: inhaled materials (plant pollen, dust mite feces)
injected materials (insect venom, drugs)
ingested materials ( peanuts, shellfish)
contacted materials (plant oil, metal)
four types of allergic/ hypersensitivity reactions Answer: type I -IV
type I Answer: antibody mediated
allergen binds to IgE on mast cell, basophils and eosinophils
cells explosively and rapidly degranulate releasing proinflammitory mediators
pollen allergy- anaphylactic shock
type II Answer: antibody mediated
small molecule binds and modifies host cell
APPHIA – Crafted with Care and Precision for Academic Excellence.
1
, B cell IgG responds to modified component on host cell
complement activation and phagocytosis causes inflammation and tissue damage
penicillin
Type III Answer: antibody mediated
antibodies respond to soluble proteins
immune complexs deposit on the walls of small blood vessels and lung tissue
inflammation
diabetics - bovine insulin and therapeutic monoclonal antibodies
type IV Answer: T cell mediated
Th1 or CD8 responds to modified proteins
response takes a few days to develop
poison ivy/ metal allergies
Type I hypersensitivity is driven by Answer: IgE driven degranulation
important defense again helminths
large size of parasitic worms makes them resistant to Answer: direct killing by CTL,
macrophages, and antibodies
mast cell degranulation Answer: immune system is directed at stimulating physiological and
behavioral mechanisms involved in expulsion from the body (diarrhea, sneezing vomiting,
scratching eat)
Type I hypersensitivity is promoted by Answer: Th2 responses
IL-4 is important isotype switching factor for IgE
IL-5 is important factor for increasing eosinophil production from bone marrow
Type I hypersensitivity degranulation is triggered by Answer: harmless antigens (allergens)
Ige and FcER1 Answer: binding of mast cells
IgE is mostly present bound to Answer: FcER1
high affinity
on mast cell in tissues
IgE is held in Answer: a rigid "shrimp" like structure through CE2 domains
CE2 domains Answer: unique to IgE
no hinge regions
APPHIA – Crafted with Care and Precision for Academic Excellence.
2