In Norway, the story of a 63-year-old man has doctors around the world talking. Nicknamed the patient from Oslohe had been living with HIV for years when a blood cancer complicated everything. To hope to survive, he had only one option: a
bone marrow transplant from a compatible donor, ultimately found within his own family.
This transplant, carried out in 2020 with his brother’s stem cells, had unexpected effects. Five years later, the cancer has disappeared and no HIV is detectable in his blood, marrow or intestines, three years after stopping antiretroviral treatments. Described in the review Nature Microbiologythis rare case affects around ten patients around the world, with a detail that intrigues researchers.
From HIV to blood cancer: the Oslo patient’s journey
Diagnosed with HIV in 2006, this man began modern antiretroviral treatment in 2010 and his viral load quickly became undetectable. Life went on as it was until 2017, when fatigue and abnormal blood tests revealed a
myelodysplastic syndromea blood cancer that depletes the bone marrow. Without a stem cell transplant, doctors believed he had very little chance of surviving.
Teams at Oslo University Hospital first looked for a donor carrying the CCR5Δ32/Δ32 mutation, which makes some people resistant to HIV, without success. They then chose his older brother, who was compatible for the transplant. The same day, surprise: tests showed that he too carried this mutation, observed in around 1% of inhabitants of Northern Europe. For the patient, “it was like winning the lottery twice“, said the patient, according to Anders Eivind Myhre, lead author of the study.
How transplantation and CCR5 turned back HIV
The CCR5 gene usually serves as a small lock on the surface of white blood cells through which HIV enters cells. With two copies of CCR5Δ32, this lock disappears almost completely. After the transplant, the patient’s immune system was replaced by that of his brother, resisting the virus in the blood and marrow.
Researchers have tracked the virus everywhere, even in intestinal biopsies, the main reservoir of HIV. Five years after the transplant, they found no active virus, no intact viral DNA in several million cells analyzed, and no HIV-specific immune response. “For all intents and purposes, we’re pretty sure he’s cured“, said Anders Eivind Myhre, who describes a man “in great shape”.
A spectacular case but a transplant too risky for everyone
Such a transplant remains reserved for blood cancers with no other outcome, with mortality and serious complications. For researchers, the interest of this case is above all to guide less dangerous approaches to eradicate HIV. “The Oslo patient may no longer be a patient. In any case, he doesn’t feel like one“, summarized Marius Troseid, co-author of the study and professor at the University of Oslo.