Lymphocytes made invulnerable to HIV infection
American scientists have managed to make mice insensitive to HIV by turning off the gene by which the virus infects lymphocytes, reports New Scientist.
Researchers from the California biotech company Sangamo BioSciences have blocked a gene encoding the CCR5 protein, which is located on the surface of T-lymphocytes and to which HIV attaches to enter the cell. To do this, they used a viral vector carrying the enzyme nuclease from the group of "zinc fingers", which specifically binds the desired gene.
Nuclease was treated with human lymphocytes, which were then injected into mice. Unchanged lymphocytes were injected into the control group of mice. Then both groups were infected with HIV. According to Philip Gregory, a representative of Sangamo BioSciences, after six weeks all the mice from the experimental group acquired resistance to HIV. Compared with the control group, they had a tenfold suppression of the virus, and there were five times more circulating T-lymphocytes.
Having received such encouraging results, scientists plan to start testing the technique on humans this year. To do this, T-lymphocytes will be taken from infected volunteers and, after switching off the CCR5 gene in the laboratory, returned back. It is expected that the offspring of these cells will acquire resistance to the virus and thereby become the dominant type of T-lymphocytes in the body. This will provide long-term protection against HIV, unlike drugs that block the CCR5 protein.