"The genie is out of the bottle"

Scientists in China used the CRISPR gene editing technique to try to cure an HIV man, what an expert called a "milestone" in the treatment of the disease.

Recognized as a groundbreaking leap forward for research and finding potential treatments for the disease, CRISPR makes DNA modification faster and easier. The technique called CRISPR-Cas9 involves the use of the protein Cas-9 to cut a specific part of the DNA.

The researchers used CRISPR to modify the stem cells of a donor and transplant them in a 27-year-old patient with HIV and leukemia. They hoped the cells would survive, reproduce, and heal the HIV man.

The approach involved the inactivation of the CCR5 gene in donor stem cells. CCR5 encodes a protein that HIV uses to penetrate human blood cells – and previous research has shown that those carrying a gene mutation are protected from HIV.

The team was able to edit 17.8% of a donor's stem cells, and the the gene-modified cells were still working 19 months after their transplant. However, they constituted 5 to 8% of the recipient's stem cells. A little over half of the mounted cells were extinct.

The team was pleased to see that the man did not seem to be suffering from the adverse effects of the transplant. The results were published in the New England Journal of Medicine.

The work was inspired by the treatment of Timothy Ray Brown. Known as the Berlin Patient, Brown had leukemia and HIV. He received a stem cell transplant to treat his cancer in 2007 and again in 2008. His donor had a CCR5 receptor mutation, which immunizes the individual against HIV. It is believed that Brown is the first person to be cured of HIV. Scientists have tried to reproduce this treatment without success.

Hongkui Deng, a biologist from Peking University in Beijing who led the study, said Nature: "It was the first test, so the most important thing was to test the security."

"Our results show proof of principle," he told The Associated Press.

Carl June, professor of immunothérapie at the University of Pennsylvania wrote an editorial in the New England Journal of Medicine criticize the work.

He told The Associated Press: "I think they have to approach 90% or more to have a chance to cure HIV." It was positive that scientists had not made a "Frankenstein cell" that would affect other genes rather than the intended target, he told the news agency.

Fyodor Urnov, a biomedical Scientists from the University of California at Berkeley who did not work on the study told Nature: "This is an important step towards using gene editing to treat human disease, I'm not surprised that five percent is not enough to reduce viral load, but we now know that published cells CRISPR can persist and we need to do better than five percent.

"With this study, we now know that these modified cells can survive in a patient and stay there."

June told The Associated Press that the approach seemed safe and accurate and that it did not raise any ethical issues.

in the NEJM On the editorial side, he argued that the speed with which the team moved from a proof of concept in animals to a human trial in two years was "striking". Such a process would take five years in the United States, he said.

"This may indicate that the regulatory environment in China allows for faster translation than that of the United States," he wrote.

"HIV-AIDS has been at the forefront of cell and gene therapy for decades, and this trend has continued in genome editing. , the genie came out of the bottle with the genome edition. "

Last year, a Chinese scientist was sentenced internationally for creating the first genetically modified babies in the world, fearing that problems could not be passed on to their children and beyond.

he Jiankui, Associate Professor at Southern University of Science and Technology Guangdong province, knocked out CCR5 from seven human embryos in a IVF to make the resulting children resistant to HIV. His experiences resulted in the birth of two twins.

But he maintained his job and said he was "proud" of what he had done, reported BBC News.