Monoclonal antibodies Flashcards
What are monoclonal antibodies (mAbs)?
- Antibodies that are clones from one parent cell.
- Specific to one type of antigen.
Describe how monoclonal antibodies are produced
1) Specific antigen injected into an animal such as a mouse.
2) B-lymphocytes producing complementary antibodies extracted.
3) B-lymphocytes fuse with myeloma cells to form hybridoma cells - these cells can divide and produce antibody.
4) Hybridoma cells cultured.
5) Monoclonal antibodies collected and purified.
Outline the uses of monoclonal antibodies
- Detection of pathogens.
- Location of cancer cells and blood clots.
- Treatment of cancer.
- Used in pregnancy test kits.
What are myeloma cells?
Type of tumour cell.
What do pregnancy kits test for?
hCG in urine.
What does a pregnancy test consist of?
A stick containing monoclonal antibodies (mAbs) specific to hCG:
- mAbs attached to a blue bead (free to move).
- mAbs fixed to the test stick.
Describe what happens to the test stick if a woman is pregnant
- hCG in urine binds to mAbs attached to a blue bead.
- mAbs with hCG diffuse up dipstick.
- mAbs fixed to the stick bind to hCG.
- Blue line forms.
Describe what happens to the test stick if a woman is not pregnant
No hCG in urine so a blue line is not formed.
What is the advantage of using monoclonal antibodies to test for pathogens?
- Specific to one particular antigen.
- Very accurate.
- Quick results.
Why can monoclonal antibodies be used to target cancer cells?
- Cancer cells have specific antigens called ‘tumour markers’ on their membranes.
- mAbs are specific to one type of antigen so can be targeted to ‘tumour markers’ without damaging other cells.
Describe how monoclonal antibodies can be used to diagnose cancer
- mAbs tagged to a radioactive substance.
- mAbs injected into the patient’s bloodstream.
- mAbs bind to ‘tumour markers’ on cancer cells.
- Emitted radiation is detected using a specialised scanner enabling doctors to determine the location of cancer cells.
How can monoclonal antibodies be used to target drugs to cancer cells?
- mAbs attached to an anti-cancer drug.
- mAbs injected into the patient’s bloodstream.
- mAbs bind to ‘tumour markers’ on cancer cells.
- Anti-cancer drug destroys cancer cells.
Why are cancer treatments that use monoclonal antibodies favoured over traditional treatments?
- Radiotherapy and chemotherapy target rapidly dividing cells.
- Healthy cells (such as half follicle cells, bone marrow cells) are damaged as a consequence, producing unpleasant side effects.
- mAbs only target cancer cells, reducing damage to normal cells.
How can monoclonal antibodies be used to located blood clots?
- mAbs tagged to a radioactive substance.
- mAbs target and bind to specific proteins in blood clots.
- Radiation emitted by mAbs is detected, enabling the location of blood clots to be identified.
