HIV infection: progress achieved in several directions at once

In Seattle (USA) there was a Conference on the issues of retroviruses and opportunistic infections - the largest forum dedicated, including HIV, and it was the fight against it that was the focus of the event.

The pathos of the meeting determined the progress achieved in several directions at once, after almost three decades the virus put scientists at a dead end by its unknowability. Many new methods have been proposed - from washing out latent HIV from cells to extracting immune cells from the body, changing them in such a way that they become resistant to the virus, and implanting back.

The stumbling block is the fact that HIV "lies" in the "reservoirs" of latent infection, and even strong drugs can not get it. "We need to first remove the virus from the latent state, and only then we will help the immune system deal with it," said Kevin De Kock, director of the Center for Global Health of the US Centers for Disease Control and Prevention.

HIV, surfaced thirty-odd years ago, has already hit more than 33 million people. Thanks to preventive measures, early diagnostics and new antiretroviral drugs, AIDS is no longer a death sentence. Nevertheless, the cost, side effects, drug resistance, etc., do not allow considering lifelong use of antiviral drugs as the ideal solution. Therefore, last year the International Society for the Fight against AIDS officially declared its task to find a panacea.

The first human trials of vaccines intended for the prevention and treatment of infection ended in disappointment. The "provirus" of HIV, embedded in the DNA of the host cell, was still inaccessible. Alas, one such provirus is sometimes enough that the infection subsequently spread throughout the body. The matter is complicated by the fact that HIV has a "reverse transcriptase", that is, it constantly mutates, and the immune system behind it simply does not keep pace. The vaccine induces the formation of antibodies that recognize and bind to very limited types of the surface of the virus.

"The development of the vaccine has been an incredibly difficult task," said John Coffin of Tufts University (USA). "But in recent years the pendulum has swung in the opposite direction." It is about the latest advances in molecular technologies that allow researchers to penetrate deeper into the mechanism of HIV infection.

For example, Dennis Burton of the Scripps Research Institute (USA) described the results of a study showing that "widely neutralizing antibodies" are able to recognize and penetrate HIV (work in this direction has been in progress for several years). And the firm Merck & Co. Presented evidence that her medicine for cancer Zolinza, also known as vorinostat, can cope with hidden HIV infection. The main thing here is that you can get to the virus. And which molecules should be used in this case is another matter.

Simultaneously, Philip Gregory of Sangamo BioSciences develops gene therapy: white blood cells with the glycoprotein CD4 are removed from the body, the gene CCR5 is turned off, by which they are exposed to HIV infection, and then return back. Cells remain so forever and produce offspring with the same characteristics.

The first test of this method gave mixed results: only one patient was cured, and the one with a natural genetic mutation. Subsequent tests will begin with the fact that HIV-infected people will undergo a course that reduces the number of lymphocytes in the bone marrow, so that GM cells with CD4 subsequently take up more space there.

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