German researchers say they have cured a man of HIV infection that could prove to be a scientific advance but researchers familiar with the work feel it is not necessarily a treatment advance, CNN reported.

Researchers at Charite University Medicine Berlin treated an HIV-infected man who had suffered from acute myeloid leukemia, a cancer of the immune system, by wiping out his own immune system with high-dose chemotherapy and radiation besides giving him a stem-cell (stem cells are immature cells) transplant that could mature into blood cells, according to a study published online last week in the journal Blood.

The HIV-infected patient had stopped taking anti-HIV medications at the time of the transplant in February 2007.

He underwent another stem-cell transplant from the same donor 13 months after a relapse of the leukemia.

Kristina Allers, one of the authors, hypothesized that HIV will nevertheless rebound over time that has not happened as the donor’s stem cells contained a rare, inherited gene mutation that made them naturally resistant to infection with HIV.

The study said the patient has showed no signs of either leukemia of HIV replication and his immune system had been restored to normal health after three-and-a-half years off of anti-HIV drugs to which the researchers concluded that cure of HIV has been achieved in this patient.

However, Dr Michael Saag, professor of medicine and director of University of Alabama at Birmingham AIDS Center says this may be a cure but it comes at a bit of a price even as AIDS researchers forecast the report will have little impact on practise.

He said the treatment could cost hundreds of thousands of dollars for each patient who gets the stem-cell transplant.

For him to receive the donor cells, his body had to have all of his immune system wiped out and then receive a bone marrow transplant. The Catch-22 here is that the best candidates for a cure, ideally, are people who are healthy and don't have leukemia,” Saag was quoted as saying.

He said the treatment associated with wiping out the immune system is very hazardous,. Even if somebody doesn't die from a transplant, there are complications that make it very unpleasant for people to live with, he said, citing graft-versus-host disease, where the infused donor cells attack the body.

In a number of cases, the transplant proves fatal.

The study is a proof of the concept that our understanding of HIV biology is correct, and that if you eliminate -- not just in theory but in practice -- all of the cells in the body that are producing HIV and replace them with uninfected cells, you have a cure, Saag said.

However, he said remaining infected with HIV is not always associated with the same grim outcome that was the norm prior to the mid-1990s, when more effective anti-HIV drugs were developed.
We can keep people alive for a normal life span. That means a 25-year-old diagnosed today with HIV has a reasonably good chance of living to 80, 85, 90, he said.

It's not going to be applicable unless they develop leukemia or lymphoma and need a bone-marrow transplant,Saag said.

Meanwhile, Dr Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases has termed the method impractical.

 It's hard enough to get a good compatible match for a transplant like this. But you also have to find (a) compatible donor that has this genetic defect, and this defect is only found in 1% of the Caucasian population and 0 percent of the black population. This is very rare, he said in a statement.

According to the World Health Organization, 33.4 million people worldwide have the virus that causes AIDS.