[BRIEF NOTE] An actual AIDS cure (?)

[rfmcdonald]

Agence France-Presse, along with The Telegraph and Deutsche Welle and numerous other news sources, carries the news that German doctors seem to have accidentally made someone HIV-positive negative again.

Doctors at a Berlin hospital said Wednesday that they appear to have rolled back the AIDS virus in a patient by using bone marrow keyed to a genetic shield against HIV, but stressed it was an unusual case that needed further investigation.

"This is an interesting case for research," said Rodolf Tauber, a professor at the Charite university clinic, where the work was carried out.

"But to promise to millions of people infected with HIV that there is hope of a cure would not be right," he said in a statement.

The patient, an American living in the German capital now 42 years old, came to the clinic three years ago suffering from leukaemia, for which he was given chemotherapy and other treatment. He had also been HIV-positive for a decade.

T-cells are derived from bone marrow.

Acting on a hunch, doctors replenished his bone marrow after the treatment by using marrow from a donor carrying a specific genetic variant known to confers some protection against HIV.

This mutation, already identified in previous research, occurs in one to three percent of the European population.

Known as Delta 32, it occurs in a gene called CCR5, on Chromosome 3.

It reduces the number of docking points, called CCR5, on the surface of so-called T immune cells targeted by the virus, thus lowering the risk of cell penetration by the pathogen.

The bone marrow donor had a double copy of the Delta variant in his genome, meaning he had inherited a copy from both his mother and his father, rather than from just one parent.

The patient was told to stop taking his HIV medication during the process, a move that would normally cause levels of HIV to rise sharply within short time.

"Today, more than 20 months after the successful transplant there is no sign of HIV in the patient," the statement said.

But the case should not lead to "false hopes", Gero Huetter, one of the members of the medical team, stressed at a news conference on Wednesday.

"This process is not adapted for the treatment of patients with HIV, neither today nor in the near future," Huetter said.

Andy Coghlan at The New Scientist website points out that this particular route is far from being suitable as a curse for the masses, not only because bone marrow transplants are themselves very risky--The Telegraph says 30% of recipients of bone marrow transplants die, Wikipedia claims more than 10%--but because the bone marrow recipient was lucky to have a significant number of matches. Others wonder whether HIV is lurking in parts of the body not detected by the hospital's various tests. Still, Coghlan argues, this clinical success points strongly towards the likelihood that emerging treatments making use of genetic engineering, making use of the genetics mentioned above, will work.