'It's promising': New breakthrough in HIV research received with enthusiasm and caution

Why, after years of intensive global research, have scientists failed to find a definitive cure for HIV-infected people ? In the infinite complexity of the issue, one of these barriers may have been overcome.

One of the reasons why the operation is so delicate lies in the virus's uneasy ability to hide within our cells, preventing it from being destroyed. Researchers have managed to find two methods to force the dormant virus to activate, as they explain in a study published in the scientific journal Nature Communications . However, these techniques have only been tested "in vitro," and it is unclear whether they will work on humans.

Today, it is possible to prevent the replication of this intruder with the help of drugs, antiretrovirals . They allow a person infected with HIV to live a normal life without developing AIDS.

But these treatments don't destroy the virus. It has the ability to create what are called reservoirs within our bodies. Dormant traces of the virus, ready to resume reproduction when treatment stops. In this latent phase, HIV is almost invisible to our immune system, harmless but impossible to destroy. But the recent discovery by Australian researchers highlights two methods for reawakening HIV, paving the way for its elimination.

"The goal is to awaken this dormant virus that forms reservoirs. To awaken it so that it can emerge from the cells it has latently infected. If we succeed, we can destroy it, either with antiretrovirals or with other immunotherapy approaches. Certain antibodies have been shown to be very effective against HIV," Victor Appay, immunology researcher and research director at Inserm, explains to BFMTV.

Getting it out? But how? Researchers have demonstrated "in vitro" the effectiveness of two cutting-edge methods. On the one hand, the technology now well-known to the general public: RNA, which has enabled the development of vaccines against Covid-19. On the other, CRISPR, sometimes referred to as "genetic scissors," a process that allows for the infinitely precise modification of a gene to induce a desired effect. In this scenario: forcing the activation of HIV.

In both cases, the result is the same: forcing the latent undesirable virus to activate and reappear on the radar. Other, less targeted approaches have been tested, without showing convincing clinical results, as Olivier Schwartz, head of the "virus and immunity" unit at the Pasteur Institute, explains. Using this method, according to the figures obtained during cell culture tests, "we observe 60 to 80% reactivation of the dormant virus," he estimates.

The researchers interviewed agree that the methods described are technically interesting. But the tone is significantly less ecstatic than that of the study's authors. "We were all there, mouths agape, like 'wow!'" the scientists told the Guardian , for example.

French specialists are more cautious. "The approach is technologically original and interesting. For now, it is completely premature to say whether there will be a clinical application, because we do not know the capacity of these new lipid nanoparticles (associated with RNA, editor's note) to reach their cellular target and reactivate the virus in the body," Olivier Schwartz cautions.

"I would say it's very elegant, innovative. They're using tools that we've only been familiar with for a few years (...) It's a great technological advance, it's promising, but I don't want to say it's revolutionary. We're still a long way from demonstrating that it's effective in both animal models and humans. There are still several barriers to overcome," Victor Appay also puts into perspective.

Many questions remain. Will the process prove effective in animals or humans? Will we truly be able to eliminate all or a sufficient portion of the virus to prevent a resurgence? With what effects? These are all questions that will require many years of additional research.