Define immunopathology
Damage caused to tissues as the result of an immune response
What are the 2 types of disease caused by the immune system?
What are hypersensitivity diseases?
Diseases that occur as a result of excessive or increased immune responses to ‘foreign’ antigens
What are autoimmune diseases?
Diseases which occur as a result of the immune system responding to ‘self’ antigens
What is type 1 hypersensitivity?
Immediate hypersensitivity
Outline the process of type 1 hypersensitivity
Give examples of type 1 hypersensitivity
How are mast cells activated?
By antigen cross-linking
What receptor for IgE do mast cells carry?
FcƐR1
What is characterstic of a local hypersensitivity reaction in the skin?
Wheal-and-Flare reaction
Why can circulatory collapse occur as a result of anaphylatic shock?
Permeability of blood vessels is increased which prevents organs from getting enough blood
What are Type II hypersensitivity reactions?
Cytotoxic/antibody-mediated
Which antigen(s) are involved in type II hypersensitivity reactions?
IgG and IgM
What occurs in type II hypersensitivity reactions?
Which type of immune reaction occurs in incompatible blood transfusions?
type II hypersensitivity reactions
What kind of antibodies are generated in the hypersensitivity reaction against bee venom?
IgE
What is the effect of histamine on blood vessels?
It increases vascular permeability
What are the local effects of bee venom?
Immediate swelling and redness at a sting site
What is the systemic response to bee venom?
Why may a systemic response occur to bee venom?
Mast cells degranulate all over the body
Which classes of immunoglobulins fix complement?
IgM and IgG
Outline the initiation of the complement cascade
What are the symptoms of haemolytic disease of the newborn?
Why?
Enlarged liver and spleen due to macrophages phagocytosing IgG coated fetal red blood cells
What are type III hypersensitivity reactions?