FAQ: Laboratory studies of HIV infection

7 facts about the study of the human immunodeficiency virus in a controlled environment

One of the most urgent problems of modern medicine - is the fight against HIV. The epidemic of the infection that leads to the disease called AIDS, captured almost all countries around the world. To date, a variety of attempts at least to limit the epidemic, to stop its spread by creating vaccines and subsequent vaccination, as well as other measures, in general, have not been successful.

When the last of the vaccine failed, adopted a consensus decision in the scientific community that we do not know the fundamental mechanisms of HIV infection, and it is the most important: to fight the infection, you need to start to understand the fundamental mechanisms of infection and on this basis to develop preventive measures. Therefore, my colleagues and I are exactly the fundamental problems of HIV infection. Why this virus is so successful from his point of view? Why deal with many other viruses, the virus remains unbeaten? To feed your immune system – buy Cyanocobalamin, Meldonium, Metaprot, IRS 19, Selank, Cerluten.

• 1.Strategy for HIV

The main reason for choosing a very successful from the point of view of the virus, of course, strategy. First, unlike the other virus infects precisely those cells that are designed to fight infection. Secondly, he chose the path of a successful sexual reproduction - is the preferred method for virus propagation. It is important that it not only infects the immune cells that are designed to fight it, and activated cells. That is, when the virus infects the other body, the immune system cells are activated and destroy the virus or virus infected cells. However, HIV attacks the activated cells, that is, the ones that are designed to destroy it - this is its advantage.

For a long time it seemed that the disease runs as follows: the virus infects a person, there are some mild symptoms, and then it disappears, and there is many months, sometimes even long-term latent phase. But then it turned out that it is not. The concept of latent phase appeared because based on a blood test sick patients. It turned out that during this phase, the virus disappears from the blood really, but it continues to multiply and destroy lymphoid tissue, lymph nodes, which are the centers of origin of the immune response to infection.

• 2.The study under controlled conditions

When it turned out, it became clear that it is necessary to study how these viruses do not proliferate in suspension in a laboratory or in the blood of a patient, namely in the tissue. Therefore, the group, which I direct, my colleagues and I have created such a laboratory system that allows you to learn in a controlled environment reproduction and pathogenesis of this virus in the lymph tissue. For a variety of both technical and ethical reasons, it is practically impossible to study how the virus replicates in the human patient tissue. A blood test can be taken without any consequences, but it is difficult to penetrate into the tissue and in many cases impossible.

From the history of medicine shows that most of the mechanisms of human diseases became clear when they were created or animals, or other laboratory models to study them, because science is necessary to control all the conditions for the study of any process. The man, of course, impossible. Animal models of HIV infection there is little, although there is a similar virus which infect monkeys, but unlike many other viruses, HIV infects human, and only a person.

We have created a system that consists of pieces of lymphatic tissue. To create it, you can take the operational material, for example, after a tonsillectomy or adenotomy when excised tonsils or adenoids. Basically cut the tonsils in children for indications of frequent colds. We take these pieces, we know how to cultivate them in the laboratory for two to three weeks, artificially infect them with HIV and see how the pathogenesis. In this way, we have some interesting data.

• 3.The use of a laboratory model

Also, this system is used for testing various antiviral drugs, because studies of HIV infection are very expensive. Any clinical trials require years of preparation, because the drug goes through various stages of testing before it is introduced even in healthy volunteers to toxicity testing. Our system allows without any problems related to ethics, with the permissions view in preclinical trials as the drug acts on the virus.

In addition, this system is very useful and provides a lot of information about the virus, transmission, experts say, that is how the virus is transmitted from an infected person to a healthy, for example from a man to a woman. We have a system that allows you to cultivate, such as the cervix, where the infecting virus transmission from man to woman sexually.

• 4.Co-infection with HIV and herpes

We got a lot of interesting results, in particular, the process of contracting the virus. HIV infects activated immune cells, some of them are moving to this state if a virus infection, but can be activated and infection by other viruses. That is why other pathogens, even not as terrible as HIV, herpes viruses such as for a healthy person, do not pose a danger, activate immune system cells, thus creating a new target for HIV infection.

• 5.The defeat of the immune response system of control

HIV "invented" a cunning strategy: it infects cells, and they begin to secrete special substances - cytokines that activate neighboring cells. Therefore, a neighboring cell, which until then had been alone and therefore could not be infected with HIV, it becomes a target for the virus. Thus HIV infection paves the way for himself and distributed in the tissues. In addition, HIV infection, and infection associated virus, activating the cells to cause the production of so-called interleukins. Interleukins - is soluble substances which are allocated among the cells are absorbed by the other during the normal immune response. It is very difficult, "degenerate" system, it can be replaced with some other interleukins, and they regulate the normal immune response. This complex system of interleukins varies under the influence of HIV infection like a sick man, and the chronically sick.

We have found for example that one odd elevated cytokine in semen of men with HIV, which is called interleukin-7. Why he's raised - it is unknown.

Knowing the nature of this virus, it is possible to think that he does nothing in vain. Most likely, the entire cytokine system is a sick man changes the virus in their favor, otherwise evolution would not let him be so successful. Perhaps more pathogenic viruses are selected than if it was without interleukin. It was found that the IL facilitates the transfer of the virus and infection of cervical tissue.

We conducted a simple experiment: if you take the tissue of the cervix of healthy women and infecting her with HIV in a Petri dish, add to the interleukin-7, the infection is much more efficient. On the basis of this work, we have the following hypothesis: maybe men with elevated IL-7 is easier to infect their partners than those who have less interleukin.

• 6.Resistance to HIV infection

Linked to this is a big problem: there are a pair of "husband - wife" recruited for clinical trials, which consist in constant communication, not change each other, but without knowing it, and do not take precautions, the men can be infected by a virus, and a woman for a few years, often many years, did not become infected. When it is found, we thought that these women have some protection mechanism and, perhaps, it will be able to play all the others. Long studied, but nothing special in these women is not found.

In light of our research, we think that the absence of infection, transmission from these men consists precisely in the fact that they have the cytokines that promote infections violated. At the moment this is only a hypothesis, which may be incorrect.

• 7.Treatment of co-infection of HIV and herpes

As already mentioned, the herpes viruses help accompany HIV infection and transmission. For quite a long time for people infected and the virus, and the other, prescribed therapy against the herpes virus, since it is clear that a single disease rather than two. In this case, registers opened in the 70's standard drug acyclovir - this is the most effective tool against the herpes virus. Acyclovir acts on several herpes viruses, including the one that usually accompanies HIV - 2 herpes virus.

we can study the mechanism of interaction of viruses in the laboratory for the study of HIV. When we started to infect tissue slices immunodeficiency virus, and herpes virus, we would like to reproduce the effect of acyclovir on the system in a controlled laboratory case. It turned out that this is possible: the use of acyclovir inhibits herpes viral infection and leads to suppression of HIV. Since we can carry out the control in our system, it was found that acyclovir can without herpes 2 directly affect HIV infection.

We are now conducting clinical trials, they are far from complete, so can not be recommended for the treatment of acyclovir, but it is one of the examples where laboratory system allows you to open that actually it would be impossible to open, studying human. Nobody can allow research on human beings, and rightly so. Also, this situation is an example of a controlled laboratory system allows you to discover the mechanisms of interaction of the virus, viral pathogenesis, which are needed to fight the virus and the development of preventive methods.