Monoclonal Antibodies Flashcards

All 13 cards in this deck

What are monoclonal antibodies?

Identical antibodies produced from a single clone of cells.

Monoclonal antibodies are specific to one binding site on one protein antigen. What does this specificity allow them to do?

Target one specific chemical, or one specific type of cell, in the body.

What are the steps to produce monoclonal antibodies?

e.g. antibodies against the hormone hCG

1. Inject the antigen (hCG) into a mouse to stimulate its lymphocytes to make the antibody.
2. Combine a lymphocyte with a tumour cell to make a hybridoma cell, then clone it to give many identical antibody-producing cells.
3. Collect and purify the antibody.

What is a hybridoma cell?

A cell made by combining a mouse lymphocyte with a tumour cell; it can both divide and make the antibody.

Why is a hybridoma cell used to make monoclonal antibodies instead of a lymphocyte alone?

Lymphocytes do not divide well, but the hybridoma divides rapidly, so it can be cloned to make large amounts of the same antibody.

True or false? In a hybridoma, it is the tumour cell that decides which antibody is made.

False. The mouse lymphocyte makes the particular antibody; the tumour cell gives the ability to divide.

What are the steps by which a monoclonal antibody pregnancy test works?

e.g. a test strip dipped in urine containing the hormone hCG

1. Urine moves up the strip, where mobile antibodies attached to a dye bind any hCG.
2. The antibody–hCG complex is trapped by fixed antibodies in the test area.
3. The dye collects there as a coloured line = positive result.

On a monoclonal antibody test strip, what is the purpose of the control area (control line)?

To show that the test is working, so a negative result is not a false negative.

What are the steps to use monoclonal antibodies to measure the level of a hormone in a blood sample?

e.g. measuring a hormone in an athlete's blood

1. Add monoclonal antibodies specific to that hormone, each carrying a label or dye.
2. The antibodies bind only to that hormone.
3. Measure the amount of colour/label bound — this gives the level of the hormone.

What are the steps to use monoclonal antibodies and a fluorescent dye to locate a specific molecule or pathogen on a microscope slide?

e.g. finding a pathogen in a throat sample

1. Bind a fluorescent dye to the monoclonal antibodies.
2. Put the dyed antibodies on the slide and rinse off any unbound antibodies.
3. The antibodies bind to the pathogen, which then shows up (fluoresces) under the microscope/UV.

In cancer treatment, what can a monoclonal antibody be bound to?

A radioactive substance, a toxic drug, or a chemical which stops cells growing and dividing.

Why can a monoclonal antibody carrying a toxic drug kill cancer cells without harming other cells in the body?

It binds only to the antigen on the cancer cells, so the drug is delivered only to them.

True or false? Monoclonal antibody treatments turned out to have fewer side effects than expected.

False. They create more side effects than expected, so they are not yet as widely used as was hoped.