Several Chinese scientists used genetic editing to cure HIV infection

Several Chinese scientists reported using the CRISPR genetic editing tool for the first time to try to cure HIV infection in a patient by providing altered blood cells resistant to the virus that causes AIDS.

That genetic editing tool has long been used in research laboratories, and a Chinese scientist faced harsh criticism last year when he revealed having applied it to embryos from which twins were born. The genetic edition of embryos is considered too risky, partly because changes to DNA can pass to future generations.

The report of several Chinese researchers released Wednesday in the New England Journal of Medicine is the first of its kind that narrates the use of CRISPR to treat a disease in an adult, where changes to DNA are confined in that person.

The attempt was effective in some aspects, but it is far from being a cure for HIV.

Anyway, it shows that the genetic edition is promising and to date it seems accurate and safe in the patient in question, said Dr. Carl June, an expert in genetics at the University of Pennsylvania who wrote a comment in the publication.

"It is very positive for the field of action," June said.

The Chinese government subsidized the investigation conducted openly with advance notice in a scientific record and ordinary informed consent procedures. Some of those steps were missing or questioned in last year's work with embryos.

"There are no ethical concerns in this case," June said.

The genetic edition permanently alters the DNA, the code of life. CRISPR is a relatively new tool that scientists can use to cut DNA at a specific place.

The new case corresponds to a 27-year-old man infected with HIV who needed a stem cell transplant to get cancer. Previously, two other men apparently were cured of both diseases by transplants from donors with natural resistance to HIV because they carry a genetic mutation that prevents that virus from entering the cells. Since these types of donors are very rare, Chinese scientists have tried to create a similar resistance against HIV by "editing" genes in blood cells in the laboratory in an attempt to mimic the mutation.

Due to the transplant, cancer in man is in remission, and cells altered to resist HIV continue to function 19 months later. However, they only represent between 5 and 8% of blood cells of that type, so they are outnumbered by those that can still be infected.

"It seems to me that they need to reach 90% or more so that they really have a chance to cure HIV," according to June.

Scientists perform various tests to increase the efficiency of genetic editing, and "our results show the evidence of feasibility" of this strategy, the study leader, Hongkui Deng, of Beijing University in Beijing wrote in an email.

In a very encouraging result, several tests show that the edition had no unintended consequences on other genes.

"One of the concerns is that they could create a Frankenstein cell, that could affect other genes and not the desired point," and it is positive that that did not happen, June said.

Source: AP