They call him ‘the patient of hope’ and, despite having contracted HIV, his body seems to have completely and forever neutralized it. It is the second case of what is known as ‘sterilizing healing’. There is not even viable DNA from the virus in the reservoirs of its cells, where HIV tends to settle in patients who, thanks to treatment, have an undetectable viral load.
There is no viable trace of the virus in the body of this patient who, as in the case of the only known precedent – the so-called ‘San Francisco Patient’, from 2020 – has not undergone a marrow stem cell transplant either. The finding has been published in the journal Annals of Internal Medicine and disseminated by the Massachusetts General Hospital (MGH) in Boston, United States.
During infection, they explain from this hospital, HIV places copies of its genome in the DNA of cells, creating what is known as a viral reservoir. In this state, the virus effectively hides itself from anti-HIV drugs and the body’s immune response.
From these reservoirs, in most people, new viral particles are constantly being produced. Antiretroviral therapy can prevent new viruses from being produced, but cannot remove the reservoir, so daily treatment is necessary to suppress the virus.
Some people, known as ‘elite controllers’, have immune systems capable of suppressing HIV without the need for medication. Although they still have viral reservoirs that can produce more HIV virus, thanks to a type of immune cell called ‘killer T cell’ they keep the virus suppressed without the need for medication.
Dr. Xu Yu, a member of the Ragon Institute at MGH, MIT and Harvard, has studied the HIV reservoirs of elite controllers. His research group identified in 2020 a patient with contracted the disease in 1992 and who did not have an intact HIV viral sequence in her genome, which indicates that her immune system may have eliminated the reservoir of HIV, it is the aforementioned ‘cure sterilizing’.
Yu’s team sequenced billions of cells from this person – 67-year-old Californian Loreen Willenberg, known as ‘San Francisco Patient’ – looking for any HIV sequences that could be used to create a new virus, and found none. This extraordinary finding, the first known incidence of a sterilizing cure without the need for medication or even a bone marrow transplant to obtain new stem cells, it was published in the magazine Nature in 2020.
Scientists have analyzed more than 1.19 billion blood cells and sequenced 500 million tissue cells.
Yu’s group now reports a second untreated HIV-infected patient, known as the Hope Patient, who, like the San Francisco Patient, does not harbor intact HIV genomes. Scientists have analyzed more than 1.19 billion blood cells and sequenced 500 million tissue cells.
“These findings, especially with the identification of a second case, indicate that there may be a course of action for a sterilizing cure for people who are not able to do it themselves,” says Yu, who is also a research physician at the Hospital. Massachusetts General.
The killer T cell response
Dr. Yu further explains that these findings suggest a specific killer T-cell response common to both patients, with the possibility that other people with HIV have also achieved a sterilizing cure. If researchers can understand the immune mechanisms underlying this response, they could develop treatments that teach other people’s immune systems to mimic them in cases of HIV infection.
Yu adds, “We are now studying the possibility of inducing this type of immunity in people on antiretroviral therapy through vaccination, with the aim of educating their immune systems to be able to control the virus without antiretroviral therapy.”