Immunology Flashcards
Macrophages are derived from what type of white blood cell?
monocytes
What are the 3 types fo antigen presenting cells?
Dendritic cells
Macrophages
B-cells
What is the role of an antigen presenting cell?
To present antigens to T-cells
How do APCs present antigens to T cells?
Via MHC class 2 molecules + type 1 and are able to stimulate CD4+ (T helper cells) and CD8+ (cytotoxic T cells)
What are non-professional antigen presenting cells?
Most cells that can ‘present’ antigens to T-cells via MHC type 1 molecules.
Tumour marker for ovarian cancer?
Ca-125
Tumour marker for breast cancer?
Ca27-29 and Ca 15-3
What is Ca125 a tumour marker for?
Ovarian cancer
Peritoneal cancer
What is Ca19.9 a tumour marker for?
Pancreatic cancer
Colon cancer
What is HCG a tumour marker for?
Trophoblastic disease
Non-eminomatous germ cell cell tumour
What is CEA a tumour marker for?
Primarily colorectal
Also raised in breast, lung and some GI cancers
What is AFP a tumour marker for?
Hepatocellular cancer
What is calcitonin a tumour marker for?
Medullary carcinoma thyroid
IgA structure?
Monomer & Dimer forms
IgA function?
Prevents pathogen colonisation of mucosal surfaces
Found on mucosal surfaces e.g. GI, GU & resp tracts
Found in secretions e.g. saliva and tears
Key in neonatal immunity as secreted in breast milk and resistant to stomach acid breakdown
IgD structure?
Monomer
IgD function?
Role as antigen receptor on B cells
IgE structure?
Monomer
IgE function?
Role in allergic response
Protestion in parasitic and fungal infections
IgG structure?
Monomer
IgG function?
Most common antibody type in circulation (approx 75% circulating Ig)
Key to fetal immunity as crosses the placenta
IgM structure?
Pentamer
IgM function?
Produced in early response to pathogens i.e. before IgG
First antibody type to be synthesized by neonates
The fetus is an allograft? T/F
True
What is an autograft/autogenous?
Where tissue is transplanted from one site on an individual to another site on the same individual
What is an allograft?
Where tissue from a different individual of the same sepcies is used.
What is a xenograft?
Where tissue from a different species is transplanted onto an individual e.g. a porcine heart valve
Type I hypersensitivity?
IgE mediated.
Fast <1hr
Antigens bind to IgE causing release of bioactive molecules.
Type I hypersensitivity examples?
Anaphylaxis
Allergic
Asthma
Atopy
Some allergies e.g. latex
Type II hypersensitivity?
IgM, IgG, complement mediated
Ig binds to host cell antigen perceived as foreign
Activates release of cytotoxic mediators e.g. MAC
Type II hypersensitivity example?
Autoimmune haemolytic anaemias
ITP
Goodpasture’s syndrome
Type III hypersensitivity?
IgG mediated.
IgG binds to antigens forming an immune complex
The immune complex often deposits in vessel walls triggering inflammatory mediators
Type III hypersensitivity examples?
SLE
Rheumatoid arthritis
Type IV hypersensitivity?
T-cell mediated
Delayed hypersensitivity
T-cells sensitised by antigens presented by APCs
Memory T cells activated after re-exposure
T-cells active macrophages
