Monoclonal Antibodies

Question 1

What are monoclonal antibodies?

Answer 1

Antibodies produced from a single group of genetically identical/cloned plasma cells

Question 2

How can monoclonal antibodies be used to target cancer cells?

Answer 2

• Monoclonal antibodies made to bind to specific tumour markers found on cancer cells
• Can attach anti-cancer drugs to the antibodies
• Antibodies bind to the tumour markers
• Specific so side effects reduced

Question 3

How can monoclonal antibodies be used in pregnancy testing?

Answer 3

• Application contains antibodies specific/complementary to the hCG protein, bound to a blue bead
• When urine is applied, hCG binds to the antibody on the beads, forming an antigen-antibody complex
• Urine moves up to the test strip, carrying beads with it
• Test strip contains immobilised antibodies to hCG
• If hCG is present, test strip turns blue because the immobilised antibody binds to the hCG-antibody complex with the blue beads attached

Question 4

What does the ELISA test for?

Answer 4

To see if a patient has antibodies/antigens specific to a certain antigen/antibody

Question 5

Direct ELISA test

Answer 5

• Immobilised antibodies attached to well
• Complimentary antigen binds to antibody, forming antigen-antibody complex
• Antibody with enzyme added
• Antibody attaches to antigen
• Substrate added, colour change if positive

Question 6

Indirect ELISA test

Answer 6

• Antigen fixed to well
• Complimentary antibody binds to antigen forming antigen-antibody complex
• Second antibody added with enzyme attached
• Antibody attaches to antigen
• Substrate added, colour change if positive