17 Aug 2011

Breakthrough in search for HIV vaccine

AIDS charities have reacted with cautious optimism to news of a breakthrough in the battle to come up with a vaccine against HIV.

HIV vaccine prototype

The scientific journal Nature has published a study by American researchers who say they have isolated 17 new antibodies which appear to fight the spread of the disease in four human patients.

Breakthrough research two years ago found similar substances in the bodies of HIV sufferers, but some of the newly isolated antibodies are almost ten times more potent.

They are classed as “broadly neutralizing antibodies” – protein molecules made by the immune system that can hunt down and kill different strains of the HIV virus.

The search for an effective vaccine against the killer disease has so far frustrated scentists because HIV changes shape so quickly, mutating into different strains in different parts of the world.

But it is hoped that studying how broadly neutralising antibodies attack different types of HIV will enable researchers to finally design an effective vaccine.

…a highly positive indicator for the eventual design of an effective antibody-based HIV vaccine.

The team behind the new study, led by Dennis Burton of the Scripps Research Institute in California, took samples from four people who had demonstrated a strong immune system response to HIV.

The found antibodies at work that were ten times more powerful than the ones previously discovered – and 100 times more potent than those first found to be effective against HIV.

It is thought that using several of the antibodies in combination could provide protection against up to 89 per cent of different strains of HIV.

The authors said their results were “a highly positive indicator for the eventual design of an effective antibody-based HIV vaccine”.

They added: “The demonstration that large numbers of potent and diverse broadly neutralizing monoclonal antibodies can be isolated from several different individuals provides grounds for renewed optimism that an antibody-based vaccine may be achievable.

There isn’t going to be a vaccine available in the near future. It is going to be a considerable period of time. Jason Warriner

But Jason Warriner, clinical director of AIDS charity the Terence Higgins Trust, told Channel 4 News we are still years away from such a breakthrough.

He said: “It’s a step forward, a step in the right direction. There is a lot a research taking place and we get these small breakthroughs from time to time.

“More research is needed and we need to pull together to pool the research that is being done.

“There isn’t going to be a vaccine available in the near future. It is going to be a considerable period of time.

“If we got one in the next ten years we would be very lucky, and that’s because of the way the HIV virus has evolved, where we’ve got so many different strains of HIV.

“So there’s cautious optimism, but we need to build on previous research and ensure that the research continues until we get the big breakthrough.”