SCIENTIFIC STAFF – A New York woman is the first woman possibly cured of HIV thanks to a transplant of umbilical cord blood stem cells resistant to this virus, which were combined with stem cells from a close relative to increase the chances of hit.
The so-called New York patient also suffered from a type of leukemia, which necessitated a bone marrow transplant, and she has been virus-free since 2017, a period which, due to other similar cases, is considered as reasonable to consider that it can be cured.
This case was reported a year ago at a medical congress, but until now the results had not been published in any scientific journal, which the team, led by the University of California (UCLA) and Johns Hopkins, done today in Cell. .
Today, four people consider themselves cured of HIV, patients from Berlin, London, Dusseldorf and now from New York. All also suffered from leukemia which required a bone marrow transplant, a risky intervention which is only indicated in hematological cancers.
The case of the New York patient, a middle-aged woman who identifies as ‘mixed race’, has several distinctive features compared to others, the first to undergo a transplant of HIV-resistant stem cells from cord blood umbilical and not from a compatible adult donor.
The team believes that the treatment has given “satisfactory long-term results”, the study says, and that the use of umbilical cord blood stem cells increases the chances of an HIV cure in people of all racial origins. .
“The HIV epidemic is racially diverse, and it is extremely rare for people of color or mixed race to find an unrelated adult donor who is sufficiently compatible,” explained Yvonne Bryson of UCLA and study co-director.
However, the use of cord blood cells “expands the possibilities for people of diverse ancestry living with HIV who need a transplant for other conditions to achieve a cure.”
Patients in Berlin, London and Dusseldorf received stem cell transplants from matched adults carrying two copies of the CCR5-delta32 mutation, a natural mutation that confers resistance to HIV by preventing the virus from entering and infecting cells.
Only about 1% of white people are homozygous for the CCR5-delta32 mutation and it is even rarer in other populations, limiting the possibility of transplanting it to patients of color, as stem cell transplants often require high donor compatibility and recipient.
These conditions made it almost impossible to find an adult donor with the aforementioned mutation and compatible with the patient, so in 2017 the team transplanted stem cells carrying CCR5-delta32/32 from stored umbilical cord blood in an attempt to simultaneously cure cancer and HIV.
The incidence of HIV among Latinos is high unlike other communities in the country.
Moreover, these cells were infused with stem cells from one of the patient’s relatives to increase the chances of success of the procedure.
“With cord blood, you don’t have as many cells and they take a little longer to populate the body after the infusion,” but using a mixture of stem cells from a parent and cord blood “gives a boost to the cells of the umbilical cord”. blood,” Bryson said.
The transplant succeeded in putting HIV and leukemia into remission, which lasted more than four years. Thirty-seven months after the transplant, the patient was able to stop taking anti-HIV drugs. Doctors following her say she has not been infected with HIV for more than 30 months since she stopped her antiviral treatment (at the time of writing the study, it was only 18 months) .
“Stem cell transplants with CCR5-delta32/32 cells offer a two-for-one cure for people living with HIV and blood cancers,” said Deborah Persaud of Johns Hopkins University and co-lead of the study, cited by Cell.
However, due to the invasive nature of the procedure, stem cell transplants (with and without the mutation) are only considered for people who need a transplant for other reasons, not to cure HIV alone. , a disease for which there are medications.
The study also highlights the importance of having CCR5-delta32/32 cells in stem cell transplants for HIV patients, since all cures, thus far, “have been with this mutated cell population. , and studies in which new stem cells that were transplanted without this mutation could not cure HIV,” Persaud said.