monoclonal antibodies

• Monoclonal antibody


  Identical antibodies made from the same B cell/plasma cell

  • antibodies manipulated to create monoclonal antibodies for medical treatment, medical diagnosis, pregnancy tests
• Ethics

  Creation of monoclonal antibodies require mice to produce antibodies and tumour cells

  Ethical debates about whether animal use is justified to benefit humans
• ELISA test (indirect)

  1. Test sample added to well (antigens fixed to well)

  2. Wash to remove unbound test sample

  3. Add antibody complementary to antigen of disease testing for

  4. Wash again to remove unbound antibody

  5. Add second antibody (with enzyme attached) complementary/binds to first antibody

  6. Wash to remove unbound second antibody

  6. Add colourless substrate until reaction occurs

  7. Colour indicates presence and quantity of antigen
• Pregnancy tests


  1. Urine is absorbed into strip, moves along pregnancy test, reaches mobile antibodies (complementary to hCG hormone, coloured dye attached)
  2. Second antibody immobile (also complementary to hCG)
  3. If most of the first antibodies bind to hCG, hCG binds to second antibody (first still attached), resulting in blue line (indicates pregnancy)
  4. If not pregnant, antibody moves along test to third antibody (immobile and complementary to first antibody) & attaches to produce second line (control to ensure test not faulty)
• Targeting medication

  • Monoclonal antibodies with (bullet) drugs attached binds to complementary antigens on outside of cancer cells (target cell)
  • delivered to cancer cells to destroy them
  • reduces harmful side effects of chemo/radiotherapy
• ELISA test (direct)


  1. Immobilised antibodies are attached to well
  2. Sample added (e.g blood plasma)
  3. If sample contains antigen, antigen-antibody complex will form
  4. Rinse to remove unbound antigens
  5. Same antibody attached with enzyme is added
  6. Rinse to remove unbound antibodies
  7. Add substate, enzyme will react with it - colour change occurs