Immunology in the clinic and research lab

Question 1

What are anti-isotypic antibodies?

Answer 1

Polyclonal or monoclonal antibodies can be produced which bind to Fc regions of particular antibody classes e.g. to IgG’s, IgA’s

Question 2

What are immunoassays?

Answer 2

Using antibody-antigen interaction to measure antibody or antigen

• using polyclonal or monoclonal antibodies
• one of anitbody or antigen labelled or tagged to allow for its detection

Eg. ELISA

Question 3

What is direct elisa?

Answer 3

• antigen on solid support
• test antibody solution linked to enzyme added
• coloured product produced can be measured by absorbance

Question 4

What is indirect elisa?

Answer 4

• antigen on solid support
• primary antibody which binds to antigen is added
• secondary antibody is added with enzyme attached - secondary antibody binds to Fc region of primary antibody

Question 5

What is a sandwich ELISA?

Answer 5

• antigens can be present in low conc
• on antibody on solid support
• test antigen solution added and removed by washing
• bound antigen is detected by addtion of another anitbody which is labelled

Question 6

How can you measure cytokine secretion?

Answer 6

Elispot

• cytokine-specific antibody bound to well
• activated T cells are added
• cytokine secreted by the T cells is captured by the antibody
• captured cytokine is revealed by a second cytokine-specific antibody which is coupled to enzyme to give a colour

Question 7

What is western blotting?

Answer 7

1) Can be used to detect antigens or antibodies
2) Used to measure size of the protein being analysed
3) Can be used to calculate protein concentration
4) May show if protein has been degraded

Protein standards of known size and concentration (‘ladder’)

Question 8

How can we track T cell responses?

Answer 8

By creating MHC complexes loaded with HIV antigen we can calculate for example what proportion of CD 8+ T cells will bind to the antigen

Question 9

How can you measure neutrophil function?

Answer 9

• Neutrophils are found in actuetly inflammed tissue - using ROS they ingest pathogens
• Neutrophil oxidative burst assay uses DHR which is oxidised by ROS - and a green fluroescence is detected showing the presence

Question 10

What does nephelometry do?

Answer 10

Used to study the amount of antibody from different classes present in serum

Question 11

How can you diagnose autoimmune disease?

Answer 11

Detection of autoantibodies