Information from GoatConnection.com|
Scientists say they have discovered why some monkeys are resistant to infection with the AIDS virus -- an exhilarating find that points to a new and highly promising strategy for blocking HIV in people.
The discovery capped a more than 10-year search for the answer to the mystery of what stops the virus cold in certain primates.
Carl Dieffenbach, director of basic science research for AIDS at the National Institutes of Health, said the finding could lead to drugs to treat AIDS infection or a vaccine to prevent it.
"This will go immediately in about 15 different directions," Dieffenbach said. "This has been an amazing year in basic research and now we've got this. We're very rich with results and we've got a lot to work on."
The discovery was reported by Dr. Joseph Sodroski and his team of Harvard University researchers at the Dana-Farber Cancer Institute in Boston. It was published in Thursday's issue of the journal Nature.
Normally, a virus spreads through the body by entering cells, hijacking their machinery and using it to make new copies of itself.
But monkeys have a protein called TRIM5-alpha that somehow is able to stop the virus from shedding its protective coat after it enters a healthy cell. The shedding of the coating is poorly understood but considered essential to the infection cycle.
Humans have their own version of TRIM5-alpha, but it is not as effective as the monkey version in countering HIV. However, researchers may be able to design a drug that makes it work better, Sodroski said.
"This is really important because it will help build a basis for hammering the virus before it gets started," said Paul Luciw, a University of California at Davis microbiologist who specializes in AIDS research.
Stephen Goff, a Columbia University biochemist and HIV expert, said: "A lot of labs are going to be working on this as soon as this paper comes out."
Sodrowski said the same mechanism may even work against other viruses.
"What we're really uncovering is the first example of a natural system of defense that may be operating against other viruses besides HIV," he said. "We're looking at 'Example 1' here, and I highly doubt it will be the only example in nature."
"It's got great potential," said Scott Wong, an Oregon Health & Science University molecular biologist who leads AIDS research on monkeys at the federal regional primate center in Oregon.
HIV belongs to a class of viruses called retroviruses that are able to permanently incorporate their genetic material into the DNA of an infected cell. Once established, the virus cannot be eliminated.
But retroviruses also are short-lived if they cannot establish a toehold, Wong said, so HIV quickly decays when the TRIM5-alpha protein blocks it from replicating in the early stage of infection.
"We knew HIV could infect monkey cells, but the infection was restricted or terminated early on," Wong said. "But nobody knew what that restriction point was, until now."