Antibodies in medicine

Question 1

True or false? Monoclonal antibodies can only bind to antigens on cells.

Answer 1

False. Monoclonal antibodies can be made to bind to a wide range of substances.

Question 2

2) Give a property of monoclonal antibodies that makes them useful in medicine.

Answer 2

E.g. they are all identical / they are very specific, only binding to a specific target substance or cell.

Question 3

The hormone human chorionic gonadotropin (hCG)
hCG antibody is found in the urine of pregnant women. The diagram shows a pregnancy test that uses antibodies for hCG. The test strip turns blue if the woman is pregnant. Suggest how the pregnancy test works.

Answer 3

E.g.

1. when urine is applied to the application area any hCG will bind to the antibody on the beads, forming an antigen-antibody complex.
2. The urine moves up the stick to the test strip, carrying any beads with it.
3. The test strip contains antibodies to hCG that are immobilised (stuck in place).
4. If there is hCG present the test strip turns blue because the immobilised antibody binds to any hCG, which concentrates the hCG-antibody complex with the blue beads attached. If no hCG is present, the beads will pass through the test area without binding to anything, and so it won’t go blue.

Question 4

What are tumor markers?

How can we utilise them?

Answer 4

The antigens found on cancer cells. they’re not found on normal body cells.
Monoclonal antibodies can be made that will bind to the tumor markers.

Question 5

Antigens on the surface of cancer cells are called tumour markers. Monoclonal antibodies can be made that bind to the tumour markers. Explain how such monoclonal antibodies could be useful for the administration of anti-cancer drugs and how this would be beneficial over administering the drug without the use of antibodies.

Answer 5

E.g. anti-cancer drugs can be attached to the antibodies that are specific to the tumour markers. When the antibodies come into contact with the cancer cells they will bind to the tumour markers. This means the drug will only accumulate in the body where there are cancer cells. So, the side effects of an antibody-based drug would be lower than if used without antibodies, because they only accumulate near specific cells.

Question 6

What is the ELISA test?

Answer 6

a medical diagnostic test that allows you to see if a patient has any antibodies to a specific antigen, or any single antibody to a certain antigen.

Question 7

What can the ELISA test be used for?

Answer 7

to test for pathogenic infections, allergies and anything you can make an antibody for.

Question 8

What are the diff. types of ELISA test?

Answer 8

Direct: uses a single antibody that is complementary to the antigen your testing for.
Indirect: uses two antibodies