Long touted as a potentially powerful weapon against HIV, stem cell therapy may be moving one step closer to reality. Researchers may soon begin using stem cell therapy in clinical trials for patients not responding to antiretroviral drugs (see related AIDS Beacon news).

At the Society for General Microbiology’s spring meeting in Edinburgh, University of Amsterdam Professor Ben Berkhout spoke of his investigations into the novel therapy.

Meant for individuals no longer responding to the traditional regimen of antivirals, Berkhout’s proposed stem cell therapy holds promise for long-term, effective results after a single treatment.

“This therapy would offer an alternative for HIV-infected patients that can no longer be treated with regular antivirals,” said Professor Berkhout in a press release. Instead, the patient’s own immune system would battle the virus.

Scientists’ interest in stem cells derives from the cells’ unique ability to renew themselves almost indefinitely. Unlike other cells, stem cells have the potential to become either a specialized cell, like a brain or heart cell, or another stem cell upon dividing.

In adults, stem cells generate replacements for cells lost during the normal course of living. For example, liver stem cells can replace damaged or dying liver cells. Theoretically, a few stem cells could be used to regenerate whole organs, although this is not yet possible with current technology.

To battle HIV, the proposed stem cell therapy involves harvesting the patient’s own stem cells from the bone marrow. After extracting the cells, doctors purify them, insert antiviral DNA into the cells, and reintroduce them back into the patient.

Once back inside the patient, the cells’ new antiviral DNA goes to work interfering with HIV’s DNA and hindering the virus’ ability to reproduce itself.

If the therapy is successful, then the antiviral DNA is passed to every generation of immune cells born from the modified stem cells, which means only one treatment would be necessary.

The treatment uses only adult stem cells, which remain relatively uncontroversial. Compared to colleagues researching embryonic stem cells, which come from human embryos and have sparked ethical concerns, scientists looking into adult stem cells generally receive unstinting support for their research.

Successful outcomes have already been reported with other adult stem cell therapies.

In 2009, German doctors declared an HIV-positive 42-year-old man, who had undergone a stem cell transplant for leukemia, free of the virus after the procedure (see the related CNN article).

Researchers are now seriously looking at stem cells as a potential avenue to a cure – a way of freeing HIV patients from the burden of a lifetime of medications to manage the disease – as a growing body of research is developing around this topic (see the related article in The Body).

Berkhout’s research team hopes to begin clinical trials within three years. “So far, very promising results have been obtained in the laboratory, and we are now testing the safety and efficacy in a pre-clinical mouse model,” said Professor Berkhout.

For more information, please see the press release on the Society for General Microbiology website.