Radiation Treatment May Help Rid Body of HIV
Early research found it lowered levels of virus to undetectable levels in blood samples from patients
TUESDAY, Dec. 3, 2013 (HealthDay News) -- In a new twist on research into ways to fight the AIDS virus, scientists say they're making progress in using radiation -- normally a treatment for cancer -- to kill HIV in the body.
"Potentially, we can eliminate all the infected cells," said study author Ekaterina Dadachova, a professor of radiology and microbiology and immunology at Albert Einstein College of Medicine of Yeshiva University in New York City.
At this point, the scientists have only managed to use radiation to vanquish the virus in blood samples. It's not clear if the treatment will work in humans, and the cost of treatment and risk of side effects are unknown.
Still, cancer patients can often tolerate radiation. And the alternative -- a lifetime on expensive anti-HIV drugs -- is quite pricey on its own.
Currently, HIV medications can force the virus into hiding but they don't kill it, and it can return to wreak havoc on the body's immune system. Scientists "have to find methods to get to those hiding infected cells, otherwise you cannot exterminate the virus in the body," Dadachova explained.
Dadachova and colleagues have spent years working on a way to kill HIV-infected cells with radiation. The idea is to use antibodies -- soldiers of the immune system that target specific invaders -- to deliver radiation to the infected cells and then destroy them.
Essentially, the radiation piggybacks on the antibodies, which are injected into the body and then find their way to the HIV-infected cells.
In the new study, the researchers tested their approach on blood samples from 15 HIV patients who were taking anti-HIV medications and found the radiation reduced the number of infected cells by 80 percent to 90 percent in most of the samples, Dadachova said.
The treatment also seems to be able to target infected cells in the nervous system, suggesting that the approach could be used to kill HIV in the brain, she said. The brain is protected by a barrier between itself and some parts of the blood that circulates in the rest of the body.
The cost of the treatment isn't clear, Dadachova said, although it may run about $15,000 per injection. As for side effects, she said the treatment shouldn't damage healthy cells because it targets the infected ones.
The next step, she said, is to test the treatment in people as part of a clinical trial.
Charles Rinaldo Jr., chair of infectious diseases and microbiology at the University of Pittsburgh Graduate School of Public Health, cautioned that it's a "big leap" to go from the current research (which also tested the ability of the radiation therapy to cross the blood/brain barrier in test tubes) to live humans.
The good news is that HIV researchers have experience using antibodies -- those immune system soldiers -- to target cells. On the other hand, radiation can cause side effects and it requires special handling.
"This approach should be viewed with interest but caution," said Rinaldo. "We are much further advanced in treating HIV infection than we were five, 10 or 15 years ago. This treatment will need to improve on that record."
The study is scheduled for presentation Wednesday at the Radiological Society of North America's annual meeting in Chicago. Research reported at meetings should be viewed as preliminary until published in a peer-reviewed medical journal.
For more about HIV, try U.S. National Library of Medicine.