5.5 Monoclonal Antibodies

Question 1

Plasma cells that produce a specific antibody can be made using…

Answer 1

An experimental animal

Question 2

Monoclonal antibodies are…

Answer 2

Identical antibodies against one specific antigen, produced by a single clone of plasma cells

Question 3

Drugs that kill cancer cells are usually…

Answer 3

Very toxic and harmful to the cells in the body not just the cancer cells (cause of unpleasant side effects)

Question 4

Scientists can make monoclonal antibodies that…

Answer 4

Bind specifically to the antigens on cancer cells

They then attach the cancer drug to the antibodies

Question 5

Theses ‘cancer’ antibodies travel…

Answer 5

In the blood until they reach the site of the cancer

Bind to the cells

Question 6

Conventional drugs are circulated in the blood ad are present in cells through the patient’s body, whereas drugs attached to the monoclonal antibodies…

Answer 6

Are targeted only at the cells that need to be destroyed

Question 7

Few treatments for cancer that involve monoclonal antibodies one is…

Answer 7

Herceptin - for breast cancet

Question 8

Monoclonal antibodies sometimes called ‘magic bullets’ because they…

Answer 8

Deliver toxic drugs only to the cells that need to be destroyed - far fewer side effects than conventional cancer drugs

Question 9

Monoclonal antibodies are also being developed to…

Answer 9

Inhibit the immune system after organ transplants

Also useful in treatment of heart disease - heparin - inhibits blood clotting to reduce the chances of coronary thrombosis occurring after a person has received angioplasty

Question 10

Main problem with using monoclonal antibodies in this way is …

Answer 10

Mouse antibodies are seen by the immune system as ‘foreign’ - there is an immune response to the monoclonal antibody

Anti-mouse antibodies are made to attach to the mouse antibodies and destroy them
Also join onto the mouse antibodies forming a complex that can cause kidney damage

Question 11

A solution to this main problem of monoclonal antibodies is…

Answer 11

To produce human monoclonal antibodies rather than using an experimental animal - GE

Question 12

Monoclonal antibodies can also be used in…

Answer 12

Test kits to detect specific antigens or antibodies that indicate disease
Very specific and quick
Some can be used by a GP so a patient can receive a test within a few minutes

Question 13

One way to detect prostate cancer is to…

Answer 13

Test blood serum to see whether it contains prostate specific antigen (PSA)
If present it is likely that the patient could have cancer and further investigations is ha as biopsy would be carried out

Question 14

1st stage of prostate test:

Answer 14

Antibodies to PSA bound to well in test plate

Question 15

2nd stage to prostate test is:

Answer 15

Blood from patient added
PSA binds to antibody
Other antigens do not bind

Question 16

3rd stage of prostate test:

Answer 16

Antibody with enzyme attached is added

This only binds to the first antibody if PSA is present

Question 17

4th stage of prostate test:

Answer 17

The second antibody binds to the antibodies with PSA attached
The well is washed to remove unbound antibodies

Question 18

5th stage of prostate test:

Answer 18

Colourless substrate for enzyme added

Question 19

6th stage of prostate test:

Answer 19

Enzyme converts colourless substrate to coloured product

Question 20

Monoclonal antibodies can be used is in…

Answer 20

Pregnancy testing kits
As soon as the embryo implants the lining of the uterus a placenta starts to form
Placenta secretes a hormone, human chorionic gonadotrophin (hCG)
Hormone is excreted in the woman’s urine
hCG is only produced by women no are pregnant - reliable way to test for pregnancy as it is only found in a woman’s urine
Woman is instructed to dip the test stick into a urine sample
If hCG is present there will be a colour change or other display change
The require monoclonal antibodies are all present on the test stick