Monoclonal Antibodies
Higher Tier Only
Production of Monoclonal Antibodies
- Monoclonal antibodies are antibodies that are made by identical immune cells, these identical immune cells are clones of the parent cell
- Antibodies are Y shaped proteins made by lymphocytes
- The antibodies are specific to one binding site on one protein antigen and so are able to target a specific chemical or specific cells in the body
- They are produced by stimulating mouse lymphocytes to make a particular antibody by exposing them to an antigen
The antigen is injected into a mouse and the antibodies combined with a tumour cell to make clones of the antibody
- The lymphocytes are combined with a particular type of tumour cell to make a hybridoma cell
- Tumour cells can divide quickly and repeatedly which is why they are used
- The hybridoma cell can both divide and produce the antibody
- Single hybridoma cells are cloned, resulting in many divisions, making high numbers of identical cells that all produce the same antibody
- A large amount of the antibody can be collected and purified ready for use
Exam Tip
The cells produced in this way create only one type of antibody, hence the prefix ‘mono_'. The antibodies come from multiple copies of the same cell, hence the suffix '_clonal'.
Monoclonal Antibody Uses
Higher Tier Only
Monoclonal antibody uses
- The cloned antibodies that are produced can be complementary to a specific protein on the cell or a particular chemical
- Monoclonal antibodies have a variety of uses, some examples include:
- In pregnancy tests
- In laboratories to measure the levels of hormones and other chemicals in blood (such as some cancer proteins), or to detect pathogens
- In diagnostic test kits such as
- Those used commonly in the Covid-19 pandemic (lateral flow tests)
- The detection of prostate cancer in men by testing for a protein (found in blood and urine) that is associated with the disease
- In research to locate or identify specific molecules in a cell or tissue by binding to them with a fluorescent dye
- To treat some diseases
- For cancer, the monoclonal antibody can be bound to a radioactive substance, a toxic drug or a chemical which stops cells growing and dividing
- It delivers the substance to the cancer cells in a targeted way, without harming nearby cells or cells in other organs and systems
Use of Monoclonal Antibodies Table
Exam Tip
You are not expected to recall any specific tests or treatments but given appropriate information, you should be able to explain how they work using the principles of antibody specificity. You should be able (in the exam) to describe some of the ways in which monoclonal antibodies can be used. You should also appreciate the power of monoclonal antibodies and be considerate of ethical issues as a result of their production and use.
