Breakthrough in the treatment of blood cancer

Genetically "trained" immune system cells are the most promising method of fighting cancer

DailyTechInfo based on Gizmag: Engineered immune cells yield "unprecedented" results in early cancer trials

Isolation of immune cells, their "training" on tumor cells and re-introduction into the body proved to be a promising approach to the fight against deadly oncological diseases. Recently, a group of researchers from the Fred Hutchinson Cancer Research Center, Seattle, announced a breakthrough in this direction. The new method has been tested on people with severe blood cancer. In comparison with previous similar experiments, unprecedented results were obtained – the proportion of patients responding to therapy was more than 93%.

The use of the capabilities of the body's own immune system has long been considered as the fourth method of combating cancer, which complements the series consisting of chemotherapy, radiotherapy and surgery. The body independently activates the immune system in the case of various infectious diseases, but the cells of malignant formations differ in their ability to hide from the attack of "predatory" immunocytes, due to which malignant formations grow at a fairly rapid pace.

Scientists have long been looking for ways to forcibly activate the immune system, which is known by the term immunotherapy. One of these methods is the extraction of T-immunocytes from the patient's body, which are the main "workers" of the immune system. With the help of genetic engineering, modifications are made in these cells that supply them with CAR molecules (chimeric antigen receptors), which are a very powerful means of detecting and combating malignant cells. When modified T-immunocytes are injected back into the body, they are already able to recognize certain proteins produced by malignant cells, after which they quickly find them, attach and effectively destroy the affected cells. But the most interesting thing is that the modified T-immunocytes, once back in the body, can multiply, and the procedure of such therapy needs to be carried out only once.

The first experimental studies were started by doctors from Seattle in 2013. They involved a group of 29 patients with advanced blood cancer. Some of these patients did not succumb to any type of treatment, others had cancer after successful treatment returned again, and all of them had only a few months of life left. Of the 29 hopeless patients who received experimental immunotherapy, 27 began stable remission. And after a second course of this immunotherapy, some patients had no traces of cancer in their bone marrow.

Currently, researchers are improving the technology of CAR modifications of T-immunocytes in order to make these cells safer for healthy tissue cells and more effective killers of malignant cells. This will allow researchers to overcome a dangerous side effect. When the upgraded T-immunocytes are reintroduced into the body, they produce a lot of cytokines, substances that help them do their job. But a sudden increase in the concentration of cytokines in the blood can cause an increase in temperature and a decrease in blood pressure, which in some cases is fraught with the death of the patient.

Researchers reduced the risk of death by injecting hopeless patients with small doses of T-immunocytes, which should not have given dangerous side effects. However, even in this case, seven patients experienced a syndrome of high concentration of cytokines so strong that doctors had to resort to intensive therapy to save their lives. However, 19 patients have not experienced any side effects and are now on their way to full recovery.

Unfortunately, this method cannot yet be considered a universal lifesaver. So far, it has shown efficacy only in patients with progressive acute lymphoblastic leukemia. Nevertheless, this approach has already demonstrated its effectiveness, and other groups of scientists will probably be able to develop similar methods to combat other types of cancer.

Portal "Eternal youth" http://vechnayamolodost.ru 01.03.2016