Over the years, many cancer treatments have been developed, but most are invasive or cause massive side effects like a loss of appetite as well as a weakened immune system. This causes a lot of problems for the patient, making it harder for them to fight off the cancer. Recently, though, a new treatment has been tested which has been able to treat some patients with leukemia that uses their own immune cells to fight the cancer.
T-cell therapy utilizes the t-cells of the patient as a boost to their immune system. T-cells are an important part of the immune system, as they are what kill cells infected with pathogens. They also make Chimeric Antigen Receptors (CARs) which are receptors that can help to kill more of the same type of pathogen. These receptors can be utilized in patients with cancer, as they would help the immune system to identify pathogens.
CAR cells are receptors on the outside of a pathogen-infected cell that make proteins able to recognize them and destroy them. T-cells manufacture this and help other t-cells identify an antigen, a certain protein, which lets it attach and destroy it.
This treatment works well for B-cell type cancers such as Acute Lymphocytic Leukemia (ALL). This is one of worst relapsing cases of cancer. If intensive chemotherapy or stem cell treatments don’t work, there are close to no other options for treatment. After extensive clinical trials, 90% of the children with this cancer had a complete recovery from ALL. Many had a complete and long lasting remission and haven’t had a recurrence since.
Though this is a miraculous treatment, there are still some devastating side effects such as cytokine release syndrome, which causes high fevers and drops in blood pressure. Cytokines are released by T-cells as a direct immune response, and while this can have side effects, it is considered an “on-target” response, meaning that the therapy is engaging new T-cells.
As the future looks forward to CAR T-cells helping ALL, many wonder if it could be adapted to solid tumors, as ALL is a blood cancer. This may not be possible, as the environment directly around the tumor doesn’t have a conditioned immune response. This would require a “super T-cell” or one that would be able to maneuver in these immune-suppressed environments. This discovery indicates that we are making promising steps towards a cure.
For more information about CAR T-cell therapy, visit cancer.gov.