In some cases, it has become possible to genetically engineer the immune system to eliminate cancers, such as T-cell leukemia, that previously failed to respond to treatment.
health
January 31, 2023
T cells and brain tumor cells. Composite color scanning electron micrograph (SEM) of T cells killing brain tumor cells. Steve Guschmeissner/Science Photo Library
One of the most amazing things about the immune system is that it works subconsciously. Not only does it fight off bacteria and viruses every day, it kills most cancers long before they become a threat. However, cancer can evade the immune system. Many cancer treatments rely on restoration of their efficacy. It’s his CAR T-cell therapy that’s garnering attention that has had dramatic results in some cancers when all the usual treatments have failed.
This incredible technology relies on T cells, immune cells that patrol our bodies and kill infected and cancer cells. T cells detect targets at receptors that protrude from their surface and bind to target proteins or fragments of proteins on the outside of other cells. What this means is that if you add the right receptors to her T cells, you can target anything, including cancer.
To achieve this, one’s own T cells are extracted and genetically engineered to express a ‘chimeric antigen receptor’. This artificial receptor is made up of her three proteins, one that recognizes cancer cell targets and two that enhance her T-cell activity.
Doctors grow these cells and return them to their owners, where they look for cells with the target protein and destroy them.
Some of the people who were initially treated are still cancer-free 10 years later.
