Immunology Flashcards
(56 cards)
What type of hypersensitivity reaction is Goodpasture’s syndrome?
Type 2 - anti-glomerular basement membrane antibodies direct against alpha3 chain of collagen IV
What immunoglobulins are involved in type 2 hypersenstivity reactions?
either IgM (natural antibodies) or IgG (preformed antibodies)
What type of hypersensitvity reaction is serum sickness and SLE?
type 3 hypersensitvity - antibody antigen complex mediated. Immune complexes are then deposited
What autoantibodies are seen in most cases of SLE?
ANA Autoantibodies
Mechanism of action of rituximab?
a monoclonal antibody targeted against CD20 on B cells
MOA of belimumab?
Binds to B-cell activating factor (BAFF)/ B-lymphocyte stimulator (BLys) leading to B cell apoptosis so can no longer contribute to autoimmune damage in Lupus
What type of hypersensitivity is type 4?
T cell mediated (delayed), eg contact dermatitis, chronic graft rejection, granuloma
What is type V hypersensitivity?
stimulatory autoantivodies, ie antibodies bind to receptors on non-immune cells like Grave’s autoantibody results in overproduction of thyroid hormones
Omalizumab MOA?
IgG1 monoclonal antibody which binds to free IgE for chronic urticaria
What is the most common cell type in circulation and first to move into tissue in an infection?
neutrophil
What cell circulates in blood surveying for missing self and becomes activated if cell is non-self?
natural killer cells
What do Th1 cells do?
lead to an increased cell-mediated response typically against intracellular bacteria (triggered by IL-12). Th1 overactivation against autoantigens will cause type IV hypersensivity reactions.
What do Th2 cells do?
Lead to a humoral immune response against extracellular parasites like helminths. (Th2 overactivation will cause type 1 hypersensitvity)
What do Th17 cells do?
They produce the cytokine IL-17 which helps to recruit neutrophils to site of infection (useful against bacteria and fungi)
What T cells have immunosuppressive effects?
TReg cells
What isn’t generated in chronic granulomatous disease?
mutation in part of NADPH oxidase means no reactive oxygen species are generated
Inheritance of chronic granulotomous disease?
mostly X-linked ( can be autosomal recessive too)
What type of immunodeficiencies are leukocyte adhesion deficiency and chronic granulomatous disease?
primary immunodeficiecies of innate immune system
What is mutated in leukocyte adhesion deficiency?
Beta2 integrin which means leukocytes can’t move into tissue
What is X-linked agammaglobulinemia?
a primary immunodeficiency - mutation in Bruton’s tyrosine kinase stops B cell maturation
What is hyper IgM syndrome?
primary IDEF where CD40 mutations means no class switching, so you have lots of IgM but low or absent IgA, IgE and IgG
What is the most common primary IDEF but which most individuals are asymptomatic?
selective IgA deficiency
What mutation causes Hyper IgE syndrome and what does it present as?
STAT3 mutation, will have facical, dental and skeletal abnormalities and eczema related problems
Most severe IDEF?
SCID - both T cell and B cell arms are missing, medical emergency straight after birth
