A virus trained to search for and destroy cancer cells
Scientists have come close to creating a viral vaccine against cancerKirill Stasevich, Compulenta
A virus has been obtained that finds cancer cells by itself and slows down the growth of a metastatic tumor without touching healthy tissues.
Our immune system must monitor cases of cancer degeneration and eliminate cells that have become alien to the body. And one of the conditions for the successful development of a tumor is its ability to suppress the immune response, to get out of harm's way. On the other hand, it is precisely because of this that tumor cells are easy prey for viruses: the immune system does not know what is happening there, and the virus can safely multiply. This could not but prompt scientists to somehow use viruses to fight cancer.
When developing such a method of treatment, the main thing is to be able to teach the virus to look for malignant cells so that after injection of viral particles they find their targets themselves, without leaving a single metastasis. According to researchers from the company Jennerex Biotherapeutics, they managed to get a virus that searches for cancer cells and kills them.
The JX-594 virus, which successfully avoids immune attacks, is endowed with a special protein that directs an immune attack on the tumor. Thus, the cancer cell dies both from the virus itself, which multiplies intensively in it, and from the "awakened" immune system. Ten days after a single injection of JX-594 to twenty–three patients with metastatic cancer, the virus completely infected cancer cells in seven of the eight subjects (of those eight who received the maximum dose of the virus - VM) without any side effects; healthy tissues were not affected by viral infection.
The green glow in the tumor tissue sample confirms,
that the infection with the therapeutic virus was successful.
Credit: Naomi De Silva – VM.
A few weeks later, half of the participants in the experiment had the tumor stopped growing, and one even decreased in size.
The researchers presented the results of the experiment in the journal Nature (Breitbach et al., Intravenous delivery of a multi-mechanistic cancer-targeted oncolytic poxvirus in humans).
It should be emphasized that this is not the first attempt to force the virus to destroy a malignant tumor, but here for the first time the fate of the virus, its behavior in the body is traced: how completely it infects cancer cells, how successfully it multiplies and whether it encroaches on healthy tissues.
The researchers intend to create a number of similar viruses to "incite" them on different types of tumors.
Colleagues urge the authors to pay more attention to the relationship of the immune system with the virus itself. After all, if the virus is affected by some mutation, and it becomes "visible" to the immune system, there will be no trace of the antitumor weapon, which will give the cancer a chance to return.
Prepared based on the materials of Technology Review: Engineered Viruses Selectively Kill Cancer Cells
Portal "Eternal youth" http://vechnayamolodost.ru02.09.2011