Prof Bob Gallo is set to embark on collaborative research into HIV here, writes Claire O'Connell
A preventative vaccine that stops HIV infecting new cells is the only way to resolve the global AIDS pandemic. That's according to the co-discoverer of the HIV virus, Prof Bob Gallo, who is currently developing a new approach to vaccinating against Aids, and who will today be appointed as a visiting professor to University College Dublin.
Prof Gallo co-discovered HIV in the early 1980s when Aids was becoming an apparent problem in the US. "In 1981 it was identified but nothing was known really, it was thought to be trivial. Half a dozen people here and there, nothing that would stir your imagination. But by early 1982 it was clear," he recalls. The following year, Prof Gallo was involved in the discovery that HIV was the culprit in Aids, infecting cells in the immune system called T-cells and disrupting them, leaving the person open to other infections.
Crucially, Prof Gallo's team managed to grow the virus in T-cells in the lab. This allowed the scientists to characterise HIV and develop a blood test to screen for infection, and Gallo has remained a central figure in HIV and AIDS research ever since. In 1996 he co-founded the Institute of Human Virology (IHV) at the University of Maryland, where he is now professor of medicine.
Most recently his focus has been on developing a vaccine against HIV, and earlier this year he received a $15 million (€10.4 million) grant from the Bill and Melinda Gates Foundation to advance a candidate vaccine that blocks the virus.
FINDING AN EFFECTIVE vaccine is central to tackling the global Aids pandemic, according to Prof Gallo. The virus has killed more than 25 million people worldwide since the early 1980s and continues to devastate populations in areas such as sub-Saharan Africa. "We need a preventative vaccine," he says. "It won't help the person infected unless we can use it therapeutically, and that's under discussion. But the preventative vaccine is the only way to answer this."
Attempts so far to develop an effective vaccine against HIV have failed, and scientists often point to the virus's changeability as the confounding factor. But Prof Gallo believes the key lies in blocking the virus's entry into T-cells. "Ninety-nine per cent of people say that mutability is the big issue. I would say that integration is the bigger problem," he says. "And ultimately I think we are solving the problem with the vaccine candidate we have at IHV."
Prof Gallo's team has engineered their putative vaccine to recognise the specific shape of the virus as it attaches to receptors on the T-cell. HIV stays in this shape for only one to two hours as it prepares to integrate into the cell, but Prof Gallo believes this window allows enough time for the antibody to move in and act as a crowbar, blocking the virus from latching on to and infecting the cell.
"We know the result. We have broad, neutralising antibodies," states Prof Gallo, adding that pharmaceutical giant Wyeth is currently looking into testing the possible vaccine. However, much is left to tease out about how the candidate vaccine might be used in practice, such as how much is needed and how it could be delivered, he notes.
THERE ARE ALSO particular hurdles when dealing with a persistent virus such as HIV. "You have to sustain the immune response. And we don't have the luxury, like we do with polio, of waiting four weeks. We have to be there on day one. So that's the challenge," he says.
In addition to developing a vaccine, Prof Gallo believes we need continued studies into new therapeutic avenues for people with HIV infection. "As long as there are infected people in the world, which will be for a long time, we need to do research on new forms of therapy because therapy can be for 30 to 60 years. So you get toxicity and you get side-effects when you have long therapy constantly, and so you need new approaches all the time."
Another track in the fight against Aids is getting drugs and education to areas of the world that need them most. Prof Gallo's institute works on the ground in HIV-ravaged countries such as Nigeria and by next year will be treating around 130,000 people worldwide. But as HIV slips from the radar in developed nations where drug therapies are available, he stresses that we need to keep the urgency of continued research in the public mind.
"There's complacency because of the therapy, and because HIV has been around for so long. But we need the people's support or there will be no money and people will forget about Aids. We need to keep it in the news and we need to have the education. But it's not sufficient. Only science will solve the problem. Every single practical advance in HIV and Aids came out of basic research."
Prof Gallo's new position at UCD will forge closer ties between the college and his institute at the University of Maryland, where UCD virologist Prof Billy Hall is already on the board of advisors. "Billy is a great and much respected scientist and our interests overlap and complement each other," says Prof Gallo. "So it's easy to collaborate."