monoclonal antibodies Flashcards
What are monoclonal antibodies
● Antibodies, made from the white blood cell lymphocytes, that are clones from one
parent cell
● very specific to one type of antigen (anything foreign)
Describe how monoclonal antibodies are
produced
- Specific antigen injected into an animal (e.g. mouse).
- B-lymphocytes producing complementary antibodies extracted.
- B-lymphocytes fuse with myeloma cells to form hybridoma cells - these cells can divide and produce antibodies.
- Hybridoma cells cultured.
- 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 (e.g. hair 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 locate 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.