OHSU teams vaccine could keep HIV at bay
Gene Therapy Institute says human trials could be several years away
A research team at Oregon Health and Science University's Vaccine and Gene Therapy Institute has taken a major step in pursuit of the development of a vaccine against human immunodeficiency virus (HIV).
The team has produced a new vaccine that appears to almost wipe out a variation of the virus in laboratory monkeys by programming the immune system to attack the virus quicker than normal.
The OHSU research will be published online Wednesday in the science journal Nature.
The key to the breakthrough is what researchers call the 'vector,' or delivery system, for the vaccine. Most vectors are designed to infect cells with the vaccine and then disappear. The OHSU team, led by Louis Picker, associate director of the Vaccine and Gene Therapy Institute, used cytomegalovirus to transport the vaccine into the monkeys' cells. Cytomegalovirus is commonly found in most people, and for the majority of people it causes no symptoms.
Because it stays in the body, researchers hypothesized, if used as a delivery system for a new vaccine it could maintain resistance against HIV.
'It's a bit like war,' says Picker, describing the way conventional vaccine delivery systems work. 'You pull all your troops back to bases. What this new vector does, basically, is keep the troops out there all the time, armed and ready to go.'
The vaccine was tested on 24 laboratory monkeys at the Oregon Primate Research Center using a monkey version of HIV called simian immunodeficiency virus, or SIV. In 13 of the 24 cases, SIV disappeared to levels that were undetectable for eight years.
But Picker warned that it could take a long time to develop a human vaccine that would be safe and effective in people with HIV. He says it could be four years before the first human trials take place.
'Making an AIDS vaccine is like looking at a Yosemite 2,000-foot cliff you want to climb,' Picker says. 'We've basically found a path to get to the top. We still have all the climbing to do.'