Immunotherapies in cancer treatment attempt to stimulate the body's own immune system to reject and destroy tumours.
Tumours in some people with advanced melanoma have disappeared after treatment with drugs that force the cells out of hiding. With this done, the patient's immune system can act to destroy the tumour, as it can now recognise the cancer.
Tumour cells tend to outfox the immune system as they find ways to camouflage themselves; they grow a ligand- a surface molecule that activates the PD-1 receptor on the T-cell, this fools the immune system to think that tumours are normal tissue.
The drugs used were one of three types of antibodies.T-cells (playing a key role in the immune response, matured in the thymus) should be able to spot these cancer cells as foreign and therefore destroy them. They act by blocking the interaction between the PD-1 receptor and the ligand.; thus allowing the immune system to recognise the tumour as cancer cells.
Another immunotherapy is to genetically engineer a patient's T-cells to recognise and destroy cancer cells. These engineered cells attack any cell with a CD19, which is a unique surface molecule to cancer cells.
