How are monoclonal antibodies used in diagnostic tests?

Monoclonal antibodies are used in diagnostic tests to detect specific antigens or proteins associated with certain diseases.

Monoclonal antibodies (mAbs) are laboratory-produced molecules that can mimic the immune system's ability to fight off harmful pathogens such as viruses. These mAbs are designed to interact with specific antigens, which are unique proteins found on the surface of these pathogens. This specificity makes them incredibly useful in diagnostic tests.

In diagnostic tests, mAbs are used to detect the presence of specific antigens or proteins that are associated with certain diseases. For example, in a pregnancy test, mAbs are used to detect the presence of human chorionic gonadotropin (hCG), a hormone produced during pregnancy. The mAbs are designed to bind to hCG if it is present in the urine sample. If the mAbs bind to hCG, it triggers a reaction that produces a visible signal, such as a colour change, indicating a positive result.

Similarly, in tests for infectious diseases such as HIV or COVID-19, mAbs are used to detect specific antigens associated with the virus. If these antigens are present in the blood sample, the mAbs will bind to them, triggering a reaction that can be detected and read by the diagnostic test.

In addition to detecting antigens, mAbs can also be used to detect antibodies produced by the body in response to an infection. This is the basis for serological testing, which can determine if a person has been previously infected with a certain pathogen.

The use of mAbs in diagnostic tests has revolutionised the field of medical diagnostics, allowing for rapid, accurate detection of a wide range of diseases. Their high specificity and sensitivity make them an invaluable tool in disease diagnosis and monitoring.