Immunology

Question 1

Macrophages are derived from what type of white blood cell?

Answer 1

monocytes

Question 2

What are the 3 types fo antigen presenting cells?

Answer 2

Dendritic cells
Macrophages
B-cells

Question 3

What is the role of an antigen presenting cell?

Answer 3

To present antigens to T-cells

Question 4

How do APCs present antigens to T cells?

Answer 4

Via MHC class 2 molecules + type 1 and are able to stimulate CD4+ (T helper cells) and CD8+ (cytotoxic T cells)

Question 5

What are non-professional antigen presenting cells?

Answer 5

Most cells that can ‘present’ antigens to T-cells via MHC type 1 molecules.

Question 6

Tumour marker for ovarian cancer?

Answer 6

Ca-125

Question 7

Tumour marker for breast cancer?

Answer 7

Ca27-29 and Ca 15-3

Question 8

What is Ca125 a tumour marker for?

Answer 8

Ovarian cancer
Peritoneal cancer

Question 9

What is Ca19.9 a tumour marker for?

Answer 9

Pancreatic cancer
Colon cancer

Question 10

What is HCG a tumour marker for?

Answer 10

Trophoblastic disease
Non-eminomatous germ cell cell tumour

Question 11

What is CEA a tumour marker for?

Answer 11

Primarily colorectal
Also raised in breast, lung and some GI cancers

Question 12

What is AFP a tumour marker for?

Answer 12

Hepatocellular cancer

Question 13

What is calcitonin a tumour marker for?

Answer 13

Medullary carcinoma thyroid

Question 14

IgA structure?

Answer 14

Monomer & Dimer forms

Question 15

IgA function?

Answer 15

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

Question 16

IgD structure?

Answer 16

Monomer

Question 17

IgD function?

Answer 17

Role as antigen receptor on B cells

Question 18

IgE structure?

Answer 18

Monomer

Question 19

IgE function?

Answer 19

Role in allergic response
Protestion in parasitic and fungal infections

Question 20

IgG structure?

Answer 20

Monomer

Question 21

IgG function?

Answer 21

Most common antibody type in circulation (approx 75% circulating Ig)
Key to fetal immunity as crosses the placenta

Question 22

IgM structure?

Answer 22

Pentamer

Question 23

IgM function?

Answer 23

Produced in early response to pathogens i.e. before IgG
First antibody type to be synthesized by neonates

Question 24

The fetus is an allograft? T/F

Answer 24

True

Question 25

What is an autograft/autogenous?

Answer 25

Where tissue is transplanted from one site on an individual to another site on the same individual

Question 26

What is an allograft?

Answer 26

Where tissue from a different individual of the same sepcies is used.

Question 27

What is a xenograft?

Answer 27

Where tissue from a different species is transplanted onto an individual e.g. a porcine heart valve

Question 28

Type I hypersensitivity?

Answer 28

IgE mediated.
Fast <1hr
Antigens bind to IgE causing release of bioactive molecules.

Question 29

Type I hypersensitivity examples?

Answer 29

Anaphylaxis
Allergic
Asthma
Atopy
Some allergies e.g. latex

Question 30

Type II hypersensitivity?

Answer 30

IgM, IgG, complement mediated
Ig binds to host cell antigen perceived as foreign
Activates release of cytotoxic mediators e.g. MAC

Question 31

Type II hypersensitivity example?

Answer 31

Autoimmune haemolytic anaemias
ITP
Goodpasture’s syndrome

Question 32

Type III hypersensitivity?

Answer 32

IgG mediated.
IgG binds to antigens forming an immune complex
The immune complex often deposits in vessel walls triggering inflammatory mediators

Question 33

Type III hypersensitivity examples?

Answer 33

SLE
Rheumatoid arthritis

Question 34

Type IV hypersensitivity?

Answer 34

T-cell mediated
Delayed hypersensitivity
T-cells sensitised by antigens presented by APCs
Memory T cells activated after re-exposure
T-cells active macrophages