Antibody find spurs fresh hopes for AIDS vaccine

Researchers have more often than not been thwarted by the viruses' ability to mutate (Reuters: Eliseo Fernandez, file photo)

Researchers in the United States have identified two powerful antibodies that are strong enough to neutralise more than 90 per cent of all known HIV strains.

In the search for ways to beat HIV/AIDS, researchers have more often than not been thwarted by the viruses' ability to mutate, but scientists led by a team at the US National Institute of Allergy and Infectious Diseases believe they have managed to solve the problem.

The institute's director of vaccine research, Dr Gary Nabel, says it was like finding a needle in a haystack.

"We looked at a total of about 25 million cells and from those 25 million found, [there were] three antibody producing cells that really fit the characteristics," he told ABC Radio National Breakfast.

The actual hunt for the valuable antibodies only took a couple of months, but Dr Nabel says the findings represent the culmination of 10 years of work and there are at least two more things to do before the job is done.

"We need to figure out how to elicit these antibodies by giving the body the right signal to make them," he said.

"The second thing is to actually use these antibodies in trials to see if they in fact prevent infection, because if we can show that then we have some confidence going forward that this is really a good vaccine target."

The path to the discovery of a vaccine for HIV/AIDS is littered with breakthrough discoveries that have ultimately failed when they reach the trial stage, but Dr Nabel says the chances of success this time are good.

"I think that building on what I expect to be a number of newer antibodies that may target other parts of the virus, we may be able to build a work chest of antibodies that really guide us to the critical parts of the virus and will lead us to an effective vaccine," he said.

But not everyone shares Dr Nabel's optimism. Professor Tony Kelleher, who works with the National Centre for HIV Epidemiology and Clinical Research at the University of New South Wales, says there are still challenges.

"It's very, very interesting from a scientific point of view. I think it is very elegant science but actually then converting those very precise observations about the structure of this antibody and the tool that has been used to pull out the antibodies and then converting that into a vaccine, there are still significant challenges there and significant timeline," he said.

On the upside, Dr Nabel believes the techniques used in identifying the antibodies may be applicable to other diseases.

"For example, hepatitis or Ebola virus or influenza virus, and we are starting to use this approach now to attack other infectious diseases," he said.

The researchers findings were published online today in the journal Science.