monoclonal antibodies

• what are monoclonal antibodies?

  1. are lots of clones of a single B-lymphocyte which means the antibodies are identical and target only one antigen
  2. needs to be mixed with a fast dividing tumour cells
  3. this creates a fuse of a mouse B-lymphocyte and a tumour cell called a hybridoma cell
  4. these cells can be cloned to produce all the same antibodies where they are collected and purified
  5. they will bind to anything you want and will only target that molecule
• what hormone does a pregnancy test detect?

  HCG (found in the urine)
• How does a pregnancy test work?

  1. the part where you wee has some antibodies (bind to hormone) with blue beads
  2. the test strip has more antibodies of this hormone stuck onto it (control)
• what will happen when it's positive?

  • HCG binds to antibodies on blue beads
  • the urine then moves up the stick carrying the hormone and beads.
  • they then bind to the antibodies on the strip turning it blue
• what will happen when the test is negative?

  1. the urine still moves up the stick carrying the beads
  2. but nothing will stick onto the test strip so it wont go blue
• How can monoclonal antibodies treat cancer?

  cancer cells have antigens (tumour markers) on their cell membranes that aren't found on normal cells

  1. in a lab make monoclonal antibodies that will bind to them
  2. an anti-cancer drug can be attached to this eg. toxic drug, radioactive substance, stops cancer cells growing
  3. this is given in a drip
  4. they target the cancer cells and binds to tumour marker and kills cancer cells only
• monoclonal antibodies can also be used:

  1. bind hormones and other chemicals in blood to measure their levels
  2. test blood samples in labs for certain pathogens
  3. locate specific molecules in cell or tissue (using fluorescent dye)
• what are the advantages scientists thought monoclonal antibodies would have?

  1. treat cancer
  2. less side-affects than other treatments because they only target specific cells
• what are the disadvantages of monoclonal antibodies?

  1. cause fever, vomiting and low blood pressure
  2. not as widely used as treatments as scientists wanted
• what are three things that can be bound to monoclonal antibodies to treat cancer?

  • toxic drugs
  • a radioactive substance
  • chemical that stops the cancer cells from growing
• how do monoclonal antibodies work to treat cancer?

  • monoclonal antibody is attached to a radioactive substance, toxin , drug or chemicals
  • monoclonal antibodies will only attach to the target antigen on cancer cells
  • so that the radioactive substance, toxin, drug or chemical will bind to cancer cells and stop them from growing/ dividing