Study Finds Ways of Training Immune System to Fight Cancer
When people become infected with bacteria or viruses, the body's immune system reacts by targeting these foreign invaders. When it comes to cancer cells, the immune system initially attacks them with T regulatory cells. After a period of time, the T regulatory cells realize that these cells, even though they are abnormal and dangerous, are a part of the system, which prompts the cells to stop attacking them. This process leads to the spreading of cancer, which would eventually kill the victim unless medical intervention happens. In order to use the immune system to help the individual, researchers studied the possibility of training the system to continue to attack cancer cells, hoping that it could be more effective in combatting cancer.
The researchers used mouse models that have been either injected with human lymphoma cells into the bloodstream or implanted under the skin in order to study how the immune system could potentially be controlled. The researchers, headed by Ronald Levy MD and Aurelien Marabelle MD, were able to use specific monoclonal antibodies to block the T regulatory cells activity. They injected the antibodies directly into the tumor site, which bind to the surface of the T regulatory cells. As a result, the body was effective in killing cancer cells.
"These monoclonal antibodies target and eliminate T regulatory cells mixed in with the tumor that dampen the immune response against it," Levy said according to Medical Xpress. "With these negative regulatory cells out of the way, the killer T cells of the immune system are unleashed to seek and destroy the cancer cells wherever they are in the body, including in the brain."
Although the researchers found success in this method, there was also one huge negative side effect. Since the antibodies block the activity of the T regulatory cells, the immune system could now attack healthy cells as well since nothing is regulating the difference between the cells and other infections.
"We have found in animal experiments that by injecting certain monoclonal antibodies into cancer in one place in the body we can trigger the immune system to fight cancer throughout the body," Levy added. "This result has the potential to change the way we use the immune system to treat cancer." The researchers hope that depending on the location of the injection of the antibodies and the dosage amount, this method could be effective in killing cancer cells only while leaving healthy cells alone. However, Levy admits that more research needs to be done.
The study was published in the Journal of Clinical Investigation.