The Antibody Factory
Higher tier: how identical antibodies are mass-produced in a lab, and how their pinpoint specificity powers pregnancy tests and cancer treatments.
Work it through together, step by step
A free interactive activity that works the method through with a class, step by step.
Start revising freeWhat you'll cover
The Antibody Factory
*(Higher tier.)* Antibodies are brilliant at one thing: locking onto a **specific** target. What if you could make **millions of identical copies** of one, and aim them wherever you wanted? That is a **monoclonal antibody**, and this module shows how they're made and used.
Identical and specific
Four words carry this whole topic, and the marks come from linking them together rather than defining them one at a time.
Why "monoclonal"?
Why are these antibodies described as **monoclonal**?
- They come from a single clone of identical cells and bind one specific antigen
- They bind to many different antigens at once
- They can only be made in a mouse
- They are made of a single atom
A clever trick
To mass-produce one antibody you hit a snag. Neither cell you have can do the job alone, but between them they have everything you need.
Build a hybridoma
Put the steps of making monoclonal antibodies into the correct order.
- Inject a mouse with the antigen so its lymphocytes make the antibody
- Collect the antibody-making lymphocytes
- Fuse each lymphocyte with a tumour cell to form a hybridoma
- Let the hybridomas divide, cloning many identical cells
- Collect and purify the monoclonal antibodies produced
Say it in one line
A _____ that makes the antibody is fused with a _____ cell to form a _____, which divides rapidly and produces the antibody _____.
How each use works
- Pregnancy test
- Measuring a hormone
- Cancer treatment
- Locating a molecule
- Detects the hormone HCG in urine
- Finds the level of a chemical in the blood
- Carries a drug directly to cancer cells
- Binds a fluorescent dye to a specific molecule
Why so precise?
Why can a monoclonal antibody deliver a drug to cancer cells without harming healthy ones?
- It binds only to a specific antigen found on the cancer cells
- It is small enough to enter only cancer cells
- It travels faster than healthy cells can react
- It attaches to any cell it touches
Design the treatment
A patient has a tumour whose cells carry an antigen that healthy cells do not. Work through the design decisions.
- Which antigen should your antibody be made to bind to?
- What should be attached to the antibody so it treats the tumour?
- The trial reports more side effects than expected. Which explanation best fits?
Weigh it up [Higher tier]
"Monoclonal antibodies should be used to treat every cancer." Evaluate that claim in about 60 words. A full-mark answer needs all three:
- why their specificity is an advantage over an ordinary drug
- at least one drawback, such as side effects proving greater than expected
- a conclusion that actually comes down on one side
In the exam
Production line complete. Grade-9 habits for monoclonal antibodies (HT): • **Sequence** production: mouse lymphocyte (makes the antibody) **fused** with a **tumour cell** → a **hybridoma** that divides and produces antibody indefinitely. • Link **monoclonal** to **identical antibodies binding one specific antigen**: that specificity is WHY they can be targeted. • They are very specific, but caused **more side effects** than hoped, so aren't yet as widely used as expected.