Science and Technology

Brazilian vaccine against HIV begins to be tested in monkeys

A major problem to make a vaccine against HIV is that it is hypervariable, say researchers

This week began testing on monkeys HIV vaccine, which is being developed by the Faculty of Medicine, University of São Paulo in partnership with Instituto Butantan. The four animals began to be immunized with the vaccine containing parts of the virus. Then, the monkeys will receive a modified virus which causes the common cold as part of studies to develop the vaccine.

According Edecio Cunha Neto, one of the researchers responsible for conducting the project, the spread of the vaccine is to use parts of the virus that do not change. A major problem of making an HIV vaccine is that it is hypervariable, points to explain the virus genome can vary up to 20% in two patients. In components we choose to put in the vaccine are only the most conserved regions of the virus, ie, those not varied from HIV to another, he said.

Besides having little variation over the viruses were selected for provoking strong reaction in the body of most people. We did what we call rational design, to embed within our vaccine mechanisms so that she was able to give an answer that worked for HIVs varied as possible and worked on a large number of people.

After testing with the four animals, experiments will be done with a group of 28 monkeys and three different types of viruses, all modified parts of HIV. The combinations of these three viruses are, even today, the best combinations to generate potent immune responses in primates. So what we will do is choose four different combinations, one that gave stronger response. And use this combination for testing in humans, explained the researcher.

If successful, the vaccine will increase the response of immunized to the virus, reducing the transmission capacity and improving the quality of life of patients. What it will do is greatly reduce the amount of virus to kill cells that are infected. But it will hardly eradicate the infection. Will block the transmission to another person, because the amount of virus will be very low.

Mindful of the recent protests against the use of animals in research, including that led to the closure of an institute in São Paulo, Wedge made a point of saying that animals are treated well. The animals in this study did not suffer in any way. Even for the procedure to collect blood or vaccinated, they are anesthetized emphasized.

The researcher also defended the use of animals in experiments. You can not replace an animal test for a culture test or lab test simpler. The test animals will observe the effect of a new vaccine, a new drug in the whole organism, said.