Antibodies In Medicine

Question 1

What is a monoclonal antibody

Answer 1

-Antibodies are produced by plasma cells which are all clones of one B-cell hence the name monoclonal (one clone).

-They are useful because they can be produced outside the body and they are reactive with only one type of antigen

Question 2

Uses of Monoclonal Antibodies

Answer 2

• To target medication to specific cell types by attaching a therapeutic drug to an antibody (radioimmunotherapy)
• Pregnancy testing
• Medical diagnosis by identifying proteins or antigen presence using the ELISA test

Question 3

Details of radioimmunotherapy

Answer 3

• Links radioactive atoms to monoclonal antibodies that deliver the radioactivity by being complimentary and only binding to antigens only found on cancer cells.
• Doctors can concentrate radiation at tumor sites, reducing the amount of radiation that reaches healthy tissue.
• Doctors can also use it to find tumours that may have spread in the body to target therapy where it is needed.

Question 4

Details of pregnancy testing

Answer 4

• Antibodies complimentary to hCG protein are bound to a coloured bead.
• hCG in urine binds to antibodies
• Urine moves up the strip carrying beads
• Immobilised antibodies which bind to hCG create first “blue line”
• Immobilised antibodies which bind to coloured beads create second “blue line” if hcG is present

Question 5

Elisa test steps

Answer 5

-HIV antigens are attached to a test well in a dish.

-A sample of blood plasma is added to the well. If HIV antibodies are present, they bind to the HIV antigen.

-The well is washed.A second antibody with an enzyme attached is then added. This binds specifically to the HIV antibody

-The well is washed again. A yellow solution is added, which changes to blue if the enzyme is present. A blue colour shows that the person has HIV antibodies