Monoclonal Antibodies Flashcards
What is a monoclonal antibody
An antibody produced from genetically identical/cloned B lymphocytes/plasma cell
They have the same tertiary structure
What can monoclonal antibodies be used for
Tagging specific molecules
Home pregnancy tests
Diagnosing infection and diseases
Drug targeting
How can monoclonal antibodies be used to treat cancer
Tumour/cancer cell may express antigens
An antibody is produced externally to the body by doctors, which is specific to the antigen on the cancer cell
They also externally couple the antibody to a cytotoxic agent (eg a radioactive substance)
The antibody - cytotoxic complex is then injected in to the patient which can then target the cancer cells and destroy them
How can monoclonal antibodies be used in pregnancy testing
Urine containing HCG is added to the test strip
Monoclonal antibodies which are mobile and labelled (dyed) bind to the HCG
Immobilised monoclonal antibodies bind to a HCG - monoclonal antibody complex
Monoclonal antibodies that have not been bound to HCG bind to an immobile monoclonal antibody, this forms the dyed line in the control window
Explain how monoclonal antibodies can be used in medical diagnosis
The monoclonal antibodies have a specific tertiary structure which is complementary to a receptor associated with the diagnosis (eg HCG in pregnancy testing)
Dye or stain will attach to the antibody and then will bind to the complementary receptor forming an antigen - antibody complex
How can monoclonal antibodies be used in ELISA testing
An antibody is immobilised on the surface of the test well
The test sample is added to the well and (if present) the corresponding antigen attaches to the immobilised antibody
The labelled (dyed) enzyme antibody is added and links to with the antigen, if its complementary to the antigen
The enzyme substrate is added and reacts with the enzyme
This causes a colour change which is proportional to the amount of antigen present
What are the ethical issues with using monoclonal antibodies
Preclinical testing on animals could cause potential stress or harm or mistreatment
Clinical trials on humans could cause harm or side effects
