Unusual discovery: An artist's impression of a white blood cell.
Credit: iStockphoto
BERLIN: 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.
Isolated case
The patient, a 42-year-old American living in the German capital, 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.
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 confer 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 three.
It reduces the number of docking points, called CCR5, on the surface of immune system T- cells targeted by the virus, thus lowering the risk of cell penetration by the pathogen.
Double copy
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.
