Monoclonal Antibodies

• Antibodies are produced by B-lymphocytes
• Lymphocytes are white blood cells
• Monoclonal antibodies are produced from a single clone of cells
• Monoclonal antibodies are specific to one binding site on one protein antigen so they are able to target a specific chemical or specific cells in the body
• Lymphocytes do not divide easily but tumour cells can be grown easily
• Monoclonal antibodies are made by

  • Stimulating mouse lymphocytes (with vaccination) to make a particular antibody
  • The lymphocytes are combined with a particular kind of tumour cell to make a cell called a hybridoma cell
  • The hybridoma cell can both divide and make the antibody
  • Single hybridoma cells are cloned to produce many identical cells that all produce the same antibody
  • A large amount of the antibody can be collected and purified
• Monoclonal antibodies

  
• Monoclonal antibodies are used for pregnancy tests

  • The antibody binds with the hormone HCG which is only found in pregnant women's urine
  • Monoclonal antibodies are attached to the end of a pregnancy test stick onto which a woman urinates
  • If she is pregnant HCG will be present in her urine and will bind to the monoclonal antibodies on the test stick
  • This will cause a change in colour or pattern which will indicate pregnancy
  • These specific monoclonal antibodies in the pregnancy test will only bind with HCG
• Monoclonal antibodies are used in laboratories to measure the levels of hormones and other chemicals in blood, or to detect pathogens
• Monoclonal antibodies can be used in research to locate or identify specific molecules in a cell or tissue by binding to them with a fluorescent dye
• Monoclonal antibodies can be used to treat diseases

  • For cancer the monoclonal antibody can be bound to a radioactive substance, a toxic drug or a chemical which stops cells growing and dividing
  • It delivers the substance to the cancer cells without harming other cells in the body
• Monoclonal antibodies create more side effects than expected ; they are not yet as widely used as everyone hoped when they were first developed