Monoclonal antibodies Flashcards
What are monoclonal antibodies?
Monoclonal antibodies are antibodies that are made by identical immune cells, these identical immune cells are clones of the parent cell
How are monoclonal antibodies made?
Stimulating mouse lymphocytes to make a particular antibody by exposing them to an antigen.
Lymphocytes are combined with a particular type of tumour cell to make a hybridoma cell (tumour cells can divide repeatedly)
Single hybridoma cells are cloned, making high quantities of identical cells that all produce the same antibody
A large amount of the antibody can be collected and purified ready for use
How are monoclonal antibodies used?
- Pregnancy tests
- Measure the levels of hormones and other chemicals in blood
- To locate or identify specific molecules in a cell or tissue by binding to them with a fluorescent dye
How are monoclonal antibodies used in pregnancy tests?
The monoclonal antibodies are specific to a hormone produces in pregnancy - HCG
In pregnancy tests what happens in the sample pad and what section is it?
This part is dipped in urine
In pregnancy tests what is in the reaction zone and what section is it?
HCG-specific antibodies are here. They are mobile and contain blue dye
In pregnancy tests what is in the result window and what section is it?
Non-mobile HCG-specific antibodies are found here
In pregnancy tests what is in the control window and what section is it?
Non-mobile antiodies complementary to the reaction zone antibodies
How do pregnancy tests work?
The individual urinates on the first section, and if HCG is present it binds to the mobile antibodies attached to blue beads to form HCG/antibody complexes.
They are carried in the flow of liquid to the second section. The stationary antibodies then bind to the HCG/antibody complexes. As they are each bound to a blue bead it results in a blue line
How are monoclonal antibodies used to measure and monitor?
They are modifies so that they will bind to the molecule you are looking for. They are also bound to fluorescent dye.
If the molecule is present in the sample, then the antibodies will bind to it and the dye can be seen
How are monoclonal antibodies used in the treatment of cancer?
Cancer cells have antigens called tumour markers.
3 ways:
1. Producing monoclonal antibodies that bind to the TUMOR MARKERS in order to stimulate the immune system to attack the cell.
- Using monoclonal antibodies to bind to the RECEPTOR SITE on the cell surface membrane of the caner cells to stop the growth- stimulating molecules from binding. Stopping the cell from dividing
- Using monoclonal antibodies to TRANSPORT toxic drugs, chemicals or radioactive substances as they can only bind to cancer cells
What are the advantages of using monoclonal antibodies?
- Only bind to specific cells meaning healthy cells are not affected
- They can be engineered to treat many different conditions
- We are now able to make human hybrid cells to reduce the change of triggering the human immune system
What are the disadvantages of using monoclonal antibodies?
- Difficult to attach monoclonal antibodies to drugs
- They are expensive to develop
- As they were produced from mice, they often trigger the immune response when used
