Glossary for understanding developments in HIV and AIDS

Only known four cases worldwide of patients who have managed to get rid of all traces of HIV in their bodies. These are very exceptional cases. So much so, in fact, their story has been made known anonymously. under such names as the Berlin patient, the London patient, the Düsseldorf patient and the New York patient. “This phenomenon is known as a sterilizing cure for HIV. It is defined as such only for those cases in which the virus is observed to have completely disappeared from the patient’s cellsThere is no trace of the viral genome left,” Blanco explains.

All the cases of sterilizing cure of HIV described so far have one thing in common. They are all HIV-infected patients who, at some point in their lives, suffered from hematological cancer and had to undergo a bone marrow transplantThe aim of this procedure is to ‘destroy’ part of the patient’s damaged cells and replace them with healthy ones. “This provides clues for further research, but in no case does it represent a viable treatment for patients. Let’s not forget that, sometimes, this type of procedure involves many risks,” the scientist comments.

Several cases of ‘functional cure of HIV’ have also been described. There are no official estimates on how many patients fit this definition but, according to scientific journals, there are at least a hundred known cases worldwide. “In these cases, we see that the patients continue to have HIV-infected cells but that the virus does not replicate. It is the equivalent of having the infection under control without the need for treatment“, explains Blanco.

The ‘functional cure’ of HIV has to do, mainly, with the. immune system of the patients themselves. Specifically, with the T-lymphocyte capacity to control virus replication. These cases are being closely studied by the scientific community to try to decipher which genetic ingredients may contribute to the control of the virus. For the moment, the studies point to a handful of genetic mutations related to different mechanisms of the immune system.

Within the cases of ‘functional cure’ of HIV, the specialists distinguish a very specific profile of patients: the elite controllers. These are people who became infected with the virus, took antiretroviral treatment in the early stages of infection and, years later, stopped the drugs. In these cases, tests show that the virus remains latent in their cells but does not spread. The case of the Barcelona patient, studied from the Hospital Clínic, would fit this profile..

A very important nuance in understanding these types of cases, Blanco explains, is that the ‘functional cure’ of these patients is not always permanent. “There are cases in which the infection flares up again and patients have to go back on antiretrovirals. This is explained because, unlike the ‘sterilizing cure’, in these cases we know that the virus has not been completely eliminated“, explains the virologist.