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Making medicines - EdexcelProduction of monoclonal antibodies - Higher

The development of drugs is a long, complicated and expensive process. Monoclonal antibodies are identical copies of an antibody. They are used in pregnancy tests and in cancer treatment.

Part of Biology (Single Science)Health, disease and the development of medicines

Production of monoclonal antibodies - Higher

Greg Foot describes how monoclonal antibodies are produced and how they work

'Mono' means one and 'clone' means identical copy. are identical copies of one type of antibody.

are proteins produced by a type of white blood called . have proteins on their surface called . When a pathogen infects the body, the lymphocytes recognise these antigens as and attack them by producing antibodies.

Antibodies bind to specific antigens on pathogens. This means that only one type of antibody will bind to a matching antigen. Scientists discovered that we could make antibodies to bind to antigens on other substances, and not just those on pathogens. Once bound the antigens - and the substances they are found on - are merged tightly together. This makes them easier to identify and deal with.

Formation of monoclonal antibodies

  1. An antigen is injected into a mouse.
  2. The mouse naturally produces lymphocytes, which produce antibodies specific to the antigen. Lymphocytes can no longer divide once it has started to make antibodies.
  3. Spleen cells which produce the lymphocytes are removed during a small operation.
  4. The spleen cells are fused with human cancerous white blood cells called to form . Cancerous cells divide indefinitely.
  5. These hybridoma cells divide and produce millions of monoclonal antibodies specific to the original antigen. The hybridoma cells have the characteristics of both the lymphocyte in producing antibodies and the cancerous cell in the ability to divide over and over again.
Diagram showing how antibodies are collected from a vaccinated mouse
Figure caption,
A mouse is injected with a vaccine containing an antigen to start the formation of antibodies