Monoclonal antibodies Flashcards
Give some examples of what monoclonal antibodies can be used for diagnostically
Pregnancy tests, Diagnosing HIV, detecting cancer cells, blood typing before transfusions and tissue typing before transplants
How can monoclonal antibodies be used to locate the position of blood clots for patients thought to have deep vein thrombosis
Inject mouse with human fibrin (main protein in blood clots), activating the plasma cells, these are collected from the mouse spleen, plasma cells are then fused with tumour cells forming hybridomas that produce antifebrin antibodies, a radioactive chemical is attached to the antibodies (producing gamma radiation), a gamma - ray camera can be used to detect the antibodies indicating where the blood clots are.
How many times are monoclonal antibodies generally used
Once
Give some examples of what monoclonal antibodies can be used for therapeutically
Treatment for rabies virus, prevention of transplanted organ rejection, autoimmune therapies (deactivate factors involved in inflammatory response), treatment for diseases (caused by overproduction of B cells), prevention of blood clotting, treatment of breast cancer, treatment of melanoma
What were the issues with using monoclonal antibodies as a treatment
Requires multiple administrations, can cause problems and initially the monoclonal antibodies were produced by mice, rabbits or other laboratory animals, causing an immune response when introduced to humans
How have scientists overcome the issues with using monoclonal antibodies as treatment
Genetically modifying the antibody polypeptide chains so amino acid sequences are human and altering the type and position of sugar groups
What is the first step of using monoclonal antibodies to detect HIV
The HIV antigen is attached to a test plate
What is the second step of using monoclonal antibodies to detect HIV
The blood sample being tested is passed over the test plate. If HIV antibodies are present they bind to the antigen. Plate is then washed
What is the third step of using monoclonal antibodies to detect HIV
A monoclonal antibody is then passed over the plate. It’s antigen is the HIV antibody and it will bind to it, if it is present. The monoclonal antibody is attached to an enzyme.
What is the fourth step of using monoclonal antibodies to detect HIV
The bound monoclonal antibody is proportional to the bound HIV antibody. A dye called chromogen is passed over the plate. The enzyme catalyses a colour change in the dye substrate. The more intense the colour on the plate the more HIV antibody present.
