Hope has been raised for millions of HIV-fighting patients, as researchers now believe that a cure may be in the pipeline.
Currently, the virus can hide at "undetectable" levels and can avoid being killed – which means that a patient can never be considered healed.
But researchers at the University of Illinois believe they have taken a step forward to completely free patients from the virus.
They say that targeting a gene in the brain could get the virus out of hiding and leave it vulnerable to the immune system and drugs.
Charities today welcomed the results, describing the results as "promising".
A study raises new hopes for a cure for HIV. Scientists believe they may be able to target the dormant-lying virus in cells where it is hidden by drugs and the immune system (stock)
Advances in medicine in the last forty years mean that patients with the virus can have unprotected sex without fear of transmitting them.
But the ultimate goal of discovering a cure for HIV, estimated to affect 37 million people around the world, has so far eluded scientists.
Even in patients who are believed to have an "undetectable" count of the virus, there are still traces of HIV that sleep effectively inside their body.
These are called latent viruses and do not cause disease, but can not be destroyed by the immune system or drugs, making it impossible to eliminate HIV.
But when these latent viruses come to life and try to attack the body, they go out of hiding and the immune system and drugs can target them directly.
The researchers, led by Professor Jie Liang, argue that the hijacking of the gene that carries HIV out of the hiding place – called Tat – could expose the virus to the immune system.
This could also allow antiretroviral drugs to attack the dormant virus by forcing it into the open, in a method known as "shock and kill".
"It is extremely difficult to eliminate latent-infected cells from their latency," said Professor Liang, a biomedical engineer.
The authors of the study even call it "the biggest obstacle for [the] eradication of HIV infection. "No existing drugs target the Tat gene circuit.
Shock and killing treatments have been tested in HIV patients using anti-cancer drugs called HDAC inhibitors, such as vorinostat and panobinostat.
However, they "have so far failed to reduce the latent reservoir," the authors wrote in their study, published in the journal PNAS.
The researchers, headquartered in the University section of Chicago, explored how to make HIV hidden inside cells visible to the immune system.
Using a computer model, the researchers studied the Tat gene under different conditions.
HIV TRANSMISSION AND PREVENTION
It is possible to obtain or transmit HIV only through specific activities, more commonly through sexual behavior and use of a needle or syringe.
The FDA has approved more than two dozen antiretroviral drugs for the treatment of HIV infection.
They are often divided into six groups because they work in different ways.
Doctors recommend taking a combination or "cocktail" of at least two of them.
Called antiretroviral therapy, or ART, can not cure HIV, but drugs can prolong life span and reduce the risk of transmission.
1) Nucleoside / Nucleotide Reverse Transcriptase Inhibitors (NRTI)
NRTIs force the virus to use faulty versions of pre-defined blocks so that infected cells can not produce more HIV.
2) Non-nucleoside reverse transcriptase inhibitors (NNRTIs)
NNRTIs bind to a specific protein so the virus can not make copies of itself.
3) Protease Inhibitors (PI)
These drugs block a protein that infected cells need to put together new copies of the virus.
4) Inhibitors of the merger
These drugs help stop HIV from entering healthy cells in the first place.
5) CCR5 antagonist
This prevents HIV from entering a healthy cell, but differently than fusion inhibitors. It blocks a specific type of "hooking" outside some cells, so the virus can not connect.
6) Inhibitors of integration
This prevents HIV from making copies of itself by blocking a key protein that allows the virus to insert its DNA into the healthy cell's DNA.
"By aiming the Tat gene circuit with drugs or small molecules to activate it, we would be able to cause more viruses to form in latently infected cells, and therefore can be destroyed by the immune system," said Professor Liang.
"Our results suggest new ways of detecting latent cells that can lead to the eradication of HIV by a host."
Virus replication is controlled by a gene called Tat, which hijacks the cell's mechanism and makes copies of HIV come out of the cell.
The immune system naturally fights this process but only when Tat is "activated" and the virus is actively replicating. When the gene is "deactivated", HIV lies dormant in the cell.
The Tat gene has a random chance of being active or inactive at any time and can switch from one to the other spontaneously.
A spokesperson for National AIDS AIDS said that developments in care research are always exciting and welcome.
Terrence Higgins Trust said: "The results of this new research are promising and it is good to see a new mechanism to eradicate the investigated HIV.
"But it's important to note that this is a very preliminary modeling that has not yet arrived at the laboratory.
"So while we hope results will help us find a cure for years to come, it will not be for a long time."
HIV progressively damages the crucial cells of the immune system, weakening the body's ability to fight infections.
Untreated, this leads to AIDS, the collective name of a series of deadly infections that the weakened immune system can not deal with.
Figures estimate that around 101,600 people are living with infection in the United Kingdom, while the toll is closer to the 1.1 million mark in the United States.
But in both countries, it is believed that about one in seven HIV-positive people is not diagnosed.
It comes after the official September data revealed that the number of new HIV cases diagnosed in the UK has fallen to its lowest since 2000.