How does HIV spread to people?

HIV, the AIDS virus (acquired immunodeficiency syndrome), a disease that has killed about 25 million people worldwide in the past 25 years, may be one of the most carefully studied viruses for up to now. But the origin of this virus has not been ascertained.

Most researchers believe that the virus is spread from animals to humans in central Africa. But a better understanding of how people get infected with this virus can help research work to find ways to treat AIDS effectively.

Scientists are studying to learn more about the origin of the HIV virus in the body that tends to favor forests in central Africa. Researchers can wake up at dawn in the hope of gathering some of the chimpanzees' drops from the tree. Antibodies in this segment have brought about the hypothesis that the HIV virus spreads to humans from Cameroon chimpanzees in the last century. HIV virus may have mutated at least twice since then. A separate group of chimpanzees in Cameroon infects a small number of local people, an HIV virus that does not cause pandemics. Gorilla excreta also suggests gorillas may be the source of the third form of HIV infection.

(Photo: Economist.com) Another research direction besides going to these tropical forests is why people are susceptible to HIV infection. This approach may bring some useful answers. In an article published in the Journal of Science on Friday June 22 , Dr. Michael Emerman of Fred Hutchinson Cancer Research Center in Seattle described how he and his colleagues looked at another virus ( called PtERV1 ) operated about a million years ago after humanity separated from chimpanzees. It seems that ancient peoples have evolved and immunized successfully with this virus , but this evolution somehow caused their children to be unable to defend themselves against HIV.

To prove this, Dr. Emerman examines the details of a particular protein in the immune system. All primates produce ' TRIM5alpha ' to protect them against viruses of the same type as HIV. But each species produces a slightly different ' TRIM5alpha ' version, which makes these species immune to the different combinations of these viruses. For example, the version that brown monkeys make is completely resistant to HIV, and the version that baboons produce slows down the replication of the virus 50 times.

First, Dr. Emerman proved that this special protein created by everyone makes them resistant to PtERV1. This is reasonable because the fragments of chimpanzees and gorillas are fragmented versions of this virus, but the human genome does not.

PTERV1 (Photo: Sciencedayly)

However, the proof for this conclusion is difficult because the PtERV1 virus has long since disappeared. Researchers have to select through hundreds of different variants of this virus genome found in chimpanzee DNA and gorillas to see what the original genome of the virus might look like. They then put a part of the genome into a virus capable of cloning only once, and using it to find a way to infect some cells. Cells with special proteins in the human body have been able to fight the virus, but cells without this protein have been infected.

But Dr. Emerman also argues that by changing an important part of TRIM5alpha protein in the human body, to make it look like the kind previously created by prehistoric humans, he will make this protein ineffective in PtERV1 antivirus. The same change also causes proteins in the human body to protect people against HIV.

In fact, every TRIM5alpha protein in primates he tested against PtERV1 or HIV, but never against both. Thus, Dr. Emerman said, by evolving to create PtERV1 anti-virus protection, the human race previously left the HIV virus contagious four million years later.

This result does not directly lead to any new methods of HIV treatment. But it gives researchers a way to explore . So far, new researchers have focused on drugs that fight the enzymes needed for HIV replication. But as the HIV virus is increasingly resistant to these new drugs, new treatments can be created by turning this particular protein into the human body into something more like the monkey-made protein. .

This is likely to be achieved for a few rich countries that use technology known as gene activation. More specifically, a molecule that simulates monkey proteins, or combines monkey proteins with proteins in the human body to turn it into the ability to recognize HIV, may lead to finding new ways to treat it. AIDS in the future.

Truong Son