Chapter 14 Stevens (Serology) Flashcards
exaggerated response to a typically harmless antigen that results in tissue injury, disease, or even death
Hypersensitivity
Devised classification system from these reaction based on their immunologic mechanism in 1960
Philip Gell and Robin Coombs
Type I Hypersensitivity other name:
Anaphylactic hypersensitivity
Type II Hypersensitivity other name:
Antibody-mediated cytotoxicity hypersensitivity
Type III Hypersensitivity other name:
Complex mediated hypersensitivity
Type IV Hypersensitivity other name:
Cell - mediated hypersensitivity
Anaphylactic hypersensitivity other name:
Immediate
Cytotoxic hypersensitivity other name:
Antibody mediated
Immune complex hypersensitivity other name:
Complement mediated
Delayed hypersensitivity other name:
T-cell Mediated
Heterologous antigen is seen in:
Type I Hypersensitivity (Anaphylactic)
Autologous and Heterologous antigen is seen in
Type II
Type III
Type IV
Time of Latency in Anaphylactic hypersensitivity
minutes
Time of Latency in Cytotoxic and immune complex hypersensitivity
Hours
Time of latency in delayed hypersensitivity
Days
Anaphylactic, Cytotoxic, Immune Complex immune reaction:
Humoral
Immune reaction of Delayed Hypersensitivity
Cellular
Immune mechanism:
Release of
mediators from
IgE-sensitized
mast cells and
basophils
Anaphylactic Hypersensitivity
Immune mechanism:
Cell destruction
caused by
antibody and
complement,
opsonization, or
ADCC
Cell function
inhibited by
antibody binding
Cytotoxic
Immune mechanism:
Antigen–antibody
complexes
activate
complement
proteins.
Neutrophils are
recruited and
release lysosomal
enzymes that
cause tissue
damage
Immune complex hypersensitivity
Immune mechanism:
Antigen Sensitized
Th1 cells release
cytokines that
recruit
macrophages and
induce
inflammation or
activate cytotoxic
T cells to cause
direct cell
damage
Delayed hypersensitivity
Presence of complement is seen in:
Cytotoxic and Immune Complex hypersensitivity
Complement found in delayed hypersensitivity
Cellular
Anaphylaxis
Allergies (food,
products
Bronchial Asthma
Hay Fever
Urticaria
Type of hypersensitivity
Type I Anaphylactic Hypersensitivity
AHA
HDN
HTR
Thrombocytopenia
Goodpasture
Pemphigus
Vulgaris
Drug Allergies
Hyperacute GVHD
Rheumatic fever
Grave’s Disease
Type II DM
Type of Hypersensitivity:
TYPE II HYPERSENSITIVITY Antibody-mediated cytotoxicity
SLE
Arthus
Serum Sickness
Dengue
SLE
RA
Post
Streptococcal
Vasculitis
Type of Hypersensitivity
TYPE III HYPERSENSITIVITY Complex mediated hypersensitivity
Dermatitis
Chrons
Celiac
Leprosy
Tuberculin
Poison Ivy
Acute GVHD
Hashimot’s
Type I DM
Type of hypersensitivity
TYPE IV HYPERSENSITIVITY Cell - mediated hypersensitivity
Serum is transferred from an allergic individual to a non-allergic individual
1967 - Immunoglobulin E was identified as the serum factor responsible for this reaction
Passive cutaneous anaphylaxis
inherited tendency to develop classic allergic responses to naturally occurring inhaled or ingested allergens
Atopy
PHASES OF TYPE I IMMUNE RESPONSE
Sensitization Phase
Activation Phase
Late Phase
Sensitization Phase of type I immune response involves
Formation of antigen -specific IgE that attaches to mast cells and basophils
Resposure to the same antigen, causing degranulation of mast cells and
basophils and release mediators
Activation phase
most abundant preformed mediator; primary mediator
Histamine
When mast cells and basophils are triggered to synthesize other reactants such as
secondary reactants
6-8 hours after exposure
Late phase
MEDIATOR for primary (preformed)
Histamine
Heparin
Eosinophil (ECF-A)
Neutrophil (NCF-A)
Proteases (tryptase, chymase)
Smooth muscle contraction, vasodilation,
increased vascular permeability
Mediator:
Histamine, Heparin
Chemotactic for eosinophil
Mediator:
Eosinophil (ECF-A)
Chemotactic for neutrophils
Mediator:
Neutrophil (NCF-A)