Antibodies show promise for HIV vaccine

Researchers attending an AIDS vaccine conference in Atlanta this week are abuzz about broadly neutralizing antibodies and their potential to prevent HIV in monkeys.

Broadly neutralizing antibodies are a handful of recently discovered human antibodies that can bind to the AIDS virus and prevent it from infecting cells. 

'People are actually capable of making antibodies that can neutralize most strains of HIV around the world.' — Alan Bernstein

New technology is allowing scientists to isolate and study these areas of the human immune system in people who have been infected for years, said Galit Alter, a Canadian HIV researcher who works at the Ragon Institute in Boston.

However, the antibodies develop too slowly to help these patients. Also, the antibodies are only found among 10 and 30 per cent of people with long-standing HIV infections.

Researchers are now trying to find a vaccine to make the immune system produce the antibodies earlier.

Scientists have long thought a successful HIV vaccine would somehow have to address all of the strains and mutations of the virus that exist in the world or even within a single infected person.

Peter Kwong of the Vaccine Research Center at the U.S. National Institutes of Health in Bethseda, Md., is one of the scientists who's helped isolate and identify broadly neutralizing antibodies, starting with one called VRC01.

"This antibody has the ability to neutralize over 90 per cent of circulating HIV isolates," Kwong said. "So one antibody by itself is able to effectively combat HIV1."

So far the research has been confined to the lab and in animal studies.

However, Alan Bernstein of the Global HIV Vaccine Enterprise in New York said the research reflects important new knowledge about the immune system and potential weaknesses of the virus.

"It says that people are actually capable of making antibodies that can neutralize most strains of HIV around the world, thousand of strains of HIV. The question then of course is how do we use this information to design a vaccine?"

The conference ended Friday.