April 12, 2002
Maize genetically modified to contain a key protein found on the surface of the monkey form of HIV has been created by US company ProdiGene. This development brings an edible, more effective, HIV vaccine for people a step closer, says the US National Institutes of Health.
The protein – SIV gp120 – is the simian form of a protein that will be used in an HIV vaccine trial on people in Thailand later in 2002. Researchers will inject a canarypox virus modified to contain HIV genes and then a booster shot of HIV gp120. Both the trial and ProdiGene’s SIV maize research are being funded by the NIH.
But the injected HIV gp120 is not expected to provoke a strong immune response in the mucosal layers of the body, whereas an ingested vaccine would. “For AIDS, a mucosal vaccine is important in two respects,” says Stuart Shapiro, of the National Institute for Allergy and Infectious Diseases, NIH, US.
“First, the HIV virus usually gets into the body through the mucosa, when it is transmitted either sexually or homosexually – so to have a good mucosal immune response is really important,” he says. “Second, a mucosal vaccine is safer than an injectable vaccine in the developing world, where needles get re-used and are not sterilized properly.”
Sarah Schlesinger, a research scientist at the International AIDS Vaccine Initiative in New York, says ProdiGene’s announcement is “wonderful news – the protein has been in short supply and hard to produce. It’s going to be very useful for vaccine science.”