a second HIV-resistant genetic mutation discovered

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A second genetic mutation providing natural immunity against the AIDS virus has been discovered. Very rare, it represents a new hope of treatment against this still incurable disease. So far, only two cases of sustainable remission have been identified in the world.

A mutation genetic extremely rare, responsible for a muscular disease affecting a hundred people, creates a immunity natural against virus of AIDS, Spanish researchers have said, hoping it will be a trail for new anti-HIV drugs. A first mutation was well known so far: the one discovered after being transmitted to the famous "patient of Berlin", Timothy Brown, cured of HIV thanks to a graft of stem cells containing a rare mutation of the gene CCR5, which confers natural immunity against this virus.

The new mutation concerns another gene (Transportine-3 or TNPO3) and is much rarer: it was discovered years ago in the same family in Spain, suffering from an ultra-rare muscular disease, called muscular dystrophy belts type 1F. Doctors found that HIV researchers were interested in the same gene separately because it plays a role in the transport of the virus inside the cells. So they contacted geneticists from Madrid, who had the idea of ​​trying to infect, in the laboratory, the blood of members of this Spanish family with the AIDS virus.

The path of healing is still long

The experiment was a surprise: lymphocytes those who had this ultra-rare muscle disease were naturally resistant to HIV. The virus could not get into it. "It helps us to understand much better the transport of the virus in the cell Explains José Alcami, the virologist at the Carlos III Health Institute in Madrid, who conducted the research published in the American journal. PLOS Pathogens.

HIV is certainly the best known of all viruses, he says, "But there is still many things we do not know well. For example, it is unclear why 5% of patients who are infected do not develop AIDS. There are mechanisms of resistance to the infection that we understand very badly ". The way is still long to exploit this fault to produce a new drug. But the discovery of this natural resistance confirms that the TNPO3 gene is another interesting target for block the road to the virus.

What you must remember

  • A second mutation providing natural resistance to the AIDS virus has been discovered.
  • More rare than that of the CCR5 gene, this mutation concerns Transportin-3 or TNPO3, responsible for a muscular disease.
  • It offers a new avenue of research for the development of a treatment.

AIDS: natural resistance to HIV opens up perspectives

Futura article with AFP Paris, published on 06/11/2014

The healing Apparently two men infected with the AIDS virus (HIV), one of which for 30 years, resulting from a natural phenomenon, opens interesting perspectives, according to the work of researchers. In these two people, the virus has been integrated into theDNA and completely neutralized.

"This is a very interesting observation and a first demonstration with the HIV of a phenomenon that nature has been able to do during evolution with other viruses ", comments Professor Yves Lévy (Inserm, Créteil, France), co-author of a study whose results are detailed in the specialized journal Clinical Microbiology and Infection. Two patients have been infected with HIV without ever having been sick or having detectable viruses in the blood, report the authors of the study. Neither of them had to be treated. "This observation represents a trail for healing", told AFP Didier Raoult, professor at the Faculty of Medicine of Marseille, specialist in microbes of the Marseille Infection Foundation of Marseille (URMITE / CNRS / Inserm / IRD).

The analysis made it possible to reconstitute the virus found in the genome of these patients. The researchers were thus able to show that it was inactivated by a system of interruptions of the information delivered by the genes of the virus. The virus has thus become unable to multiply but remains present inside the DNA of the patients. These interruptions would be due to enzyme known, theapobec, which is part of the arsenal of humans to fight the virus, but which is usually inactivated by a protein of the virus (the "Vif" protein).

A cure by endogenization of the virus

This work opens up prospects for healing through the use or stimulation of this enzyme and also prospects of detection for newly infected patients who have a chance to heal spontaneously, according to the authors. For Professor Raoult, it could also lead to revisiting the very definition of healing that currently relies solely on the idea of ​​ridding the body of the virus.

HIV infection was more than 30 years old for the 57-year-old patient, diagnosed in 1985. He also appears to be immune to a new infection. The seropositivity the second, a 23-year-old Chilean, was identified in 2011, although he was probably infected three years ago in South America. None had other known factors for HIV resistance (lock mutation, CCR5, which allows HIV to infect cells).

This work is based on the assumption that the AIDS virus, which is a retrovirus integrating into theDNA human, may have the same fate as the hundreds of retroviruses that have already been integrated into the DNAs of mammals, including Man. This hypothesis also comes from an observation made in Koala bears that a monkey virus, cause of cancers and of leukemia, makes more sick after the integration and neutralization of the virus in their genome, says Professor Raoult.

" At the Koala bears become resistant to this Gibbon virus, by the same phenomenon of integration or endogenization, the resistant is transmissible to the offspring ", says Professor Raoult. For researchers, this mechanism was probably very common duringepidemics preceding. They therefore felt logical to think that it would occur in a number of patients infected with the AIDS virus.

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