Uses, Benefits & Limitations of Monoclonal Antibodies | Biology for Grade 10 PDF Download

Uses of Monoclonal Antibodies

• Higher tier only
• The cloned antibodies that are produced can be 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 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 without harming other cells in the body

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 to describe some of the ways in which monoclonal antibodies can be used in the exam. You should also appreciate the power of monoclonal antibodies and be considerate of ethical issues as a result of their production and use.

Advantages & Disadvantages of Monoclonal Antibodies

Higher tier only

• Monoclonal antibodies have the potential to make big improvements to diagnosis and treatment and when they were first developed there were hopes for their use to become widespread
• However monoclonal antibodies create more side effects than expected which has hampered their use

Monoclonal antibodies table

Exam Tip: You need to be able to evaluate the advantages and disadvantages of monoclonal antibodies.

Benefits, limits & ethical issues of monoclonal antibodies - Higher

Benefits
Monoclonal antibodies can be designed to bind to, and identify, almost any substance. They can be used for many purposes:

• testing for pregnancy by detecting HCG hormones in urine
• testing for diseases such herpes and chlamydia, and HIV which can lead to the development of AIDS
• to treat conditions like cancer by carrying drugs directly to the tumour cells, and helping the immune system attack them
• monoclonal antibodies can be produced quickly despite the fact that it can be time consuming when they are made for the first time

Limitations

• The human body is very complicated. Scientists originally thought that monoclonal antibodies would be a 'magic bullet' and would be able to identify and treat many medical conditions. Tests have revealed, however, that this is not the case. The interactions in the human body has resulted in unwanted side effects. This means they are not as widely used by doctors as originally thought.
  Monoclonal antibodies are also very expensive to produce.

Ethical issues

• An ethical issue is one in which people disagree for religious or other moral reasons. The first step in making a monoclonal antibody is to inject a mouse with an antigen. After it has produced antibodies, a small operation removes spleen cells, which then continue make the antibodies. Some people disagree with this use of animals to produce monoclonal antibodies
• In 2006 a drug trial involving humans using monoclonal antibodies to treat conditions such as arthritis and leukaemia went wrong. Despite the individuals being given very low doses, it resulted in organ failure but was not fatal. The monoclonal antibodies had been safely used in other animal trials before being used in human trials. This is an example of how careful we must be during drug development.