World Half Full
Second woman may have cured herself of HIV
A woman in Argentina has become only the second documented person whose own immune system may have cured her of HIV. Researchers have dubbed the 30-year-old mother, who was first diagnosed with HIV in 2013, the “Esperanza patient”, after the town in Argentina where she lives. In English, “esperanza” means “hope”.
“I enjoy being healthy,” the Esperanza patient, who spoke on condition of anonymity due to the stigma associated with HIV, told NBC News in Spanish via email. “I have a healthy family. I don’t have to medicate, and I live as though nothing has happened. This already is a privilege.”
“This is really the miracle of the human immune system,” says Dr Xu Yu, a viral immunologist at the Ragon Institute in Boston, who with Dr Natalia Laufer, a physician scientist at Argentina’s INBIRS Institute in Buenos Aries, led the exhaustive search for any viable HIV in the woman’s body. Their findings were published in the Annals of Internal Medicine.
Not only could the team find no viable HIV in a search of the Esperanza patient’s 1.2 billion blood cells, they also searched 500 million placenta-tissue cells after the woman gave birth to an HIV-negative baby in March 2020 — even using highly sophisticated and sensitive genetic-sequencing techniques that have only recently become available.
“Now we have to figure out the mechanisms,” says Dr Steven Deeks, a prominent HIV cure researcher at University of California, San Francisco, who was not involved in the study. “How does this happen? And how can we recapitulate this therapeutically in everybody?”
To date, two other people have been successfully cured therapeutically — in both cases through complex stem cell transplants.
Yu was also lead author of a paper published in Nature in August 2020 that analysed 64 people who, like the Esperanza patient, are so-called elite controllers of HIV. These are among the estimated 1 in 200 people with HIV whose own immune systems are somehow able to suppress the virus’s replication to very low levels without drugs (antiretrovirals) or even destroy the capacity of cells that harbour HIV to produce viable copies of the virus.
Take, for example, Loreen Willenberg, a now-67-year-old Californian who was diagnosed with HIV in 1992, whose immune system it appears has also eradicated the virus entirely. Even after sequencing billions of her cells, scientists couldn’t find any intact viral sequences.
Willenberg’s case of an apparent natural cure of HIV is quite similar to the Esperanza patient’s, according to Yu, who theorises that both women may have mounted a particularly potent killer T-cell response to the virus, which researchers one day hope will develop into an effective therapy.
There are a number of documented cases of people who have stopped antiretroviral treatment, and who haven’t seen their viral load rebound for years.
“We’re never going to be 100 percent sure there’s absolutely no intact virus, no functional virus anywhere in her body,” Yu says of the Esperanza patient. “To bring what we learn from these patients to a broader patient population is our ultimate goal.”
Also inspiring the HIV-cure research field are the cases of two men — the American Timothy Ray Brown and Londoner Adam Castillejo — who received stem cell transplants to treat acute myeloid leukaemia and Hodgkin lymphoma, respectively, from donors with a rare genetic abnormality that made their immune cells resistant to HIV. The University of Cambridge’s Ravindra K. Gupta, the lead author of Castillejo’s case study, says with more than four years having passed since Castillejo’s stem cell treatment with no sign of a resurgent virus, he’s now ready to assert for the first time the British man was almost definitely — as opposed to probably — cured of HIV. In 2019, Björn Jensen, of Düsseldorf University Hospital, presented the case of a third man, known as the Düsseldorf patient, who had likely also been similarly cured. This man has not experienced a viral rebound three years after being taken off his antiretroviral treatment.
It’s estimated 38 million people live with HIV globally.
ABOVE Dr Xu Yu