Monoclonal Antibodies

• What are monoclonal antibodies?

  Antibodies that can be isolated and cloned.
• What are the functions of monoclonal antibodies?

  Target specific antigens, medical diagnosis, and testing for pregnancy.
• What cells are monoclonal antibodies used to treatt?

  Cancer.
• How is cancer treated with direct monoclonal antibody therapy?

  Monoclonal antibodies specific to antigens on cancer cells are produced, they are given to a patient and attach to cancer cell receptors which block the chemical signals that stimulate their uncontrollable growth.
• What antibody is used to treat breast cancer?

  Herceptin.
• What is the advantage of direct monoclonal antibody therapy?

  As the antibodies are not toxic and highly specific, the lead to fewer side effects than other forms of therapy.
• What is indirect monoclonal antibody therapy?

  A method of attaching a radioactive or cytotoxic drug to the monoclonal antibody for it to kill the cell when attaching to it.
• Why are indirectly used monoclonal antibodies referred to as magic bullets?

  They are used in smaller doses and target specific sites.
• What is the advantage of giving indirect monoclonal antibody therapy in small quantities?

  It is cheaper and reduces any side effects it might have.
• How are monoclonal antibodies used for mediacal diagnosis?

  They interact with specific antigens and obtain a measure of the level of this antigen in the body.
• What hormone is present in a woman's urine when she is pregnant?

  Human chorionic gonadotropin (hCG).
• How does a pregnancy testing kit work?

  Monoclonal antibodies present on the test strip are linked to colored particles, then if hCG is present in the urine it binds to these antibodies creating a hCG-antibody-color complex that moves along the strip.
• Why is there an ethical debate over the production of monoclonal antibodies?

  Creating them requires mice.
• What does ELISA stand for?

  Enzyme-linked immunosorbent assay.
• How does an ELISA pregnancy test work?

  The hCG hormone present in a pregnant woman is complementary to the antibodies in a test strip. If the hCG antigen is present it binds to the first mobile antibody which is attached to a dye. This antibody-antigen complex then binds to a second immobilised antibody which gives off its dye. The mobile antibody will also bind to a third immobilised antibody and give off its dye again. This antibody is to test whether the pregnancy strip is working.
• How many antibodies are present in a pregnancy/elisa test and what are they for?

  Three antibodies present, the first binds to the antigen and moves down the strip, the second binds to the first antibody but only if the antigen is present (if she is pregnant), and the last is to bind to the first antibody to check it has moved down the strip (if the test is working).