Wednesday, March 02, 2005
Advance in virology: OPAL
The researchers initially set out to develop a technique for measuring the effectiveness of a HIV vaccine. They first extracted blood from previously vaccinated animals and then coated the cells with HIV peptide markers (a technique which only takes an hour to complete).It seems so obvious, now that they've found it.
In a normal situation, when HIV or any virus infects a cell, it leaves behind tell-tale markers or peptides on the cell surfaces which tell the immune system that the cell is infected. In this study, the researchers did not infect the animals with HIV, but rather created the illusion to the body that these cells were infected because they had the tell-tale markers (peptides) on their surface.
When they injected this peptide-coated blood back into the vaccinated animals they found that it triggered a huge immune response.
“When we analysed HIV-specific immunity in the weeks following the assays (peptide-coating), a marked enhancement of virus-specific immunity was induced,” Associate Professor Kent says.
“The technique was also effective for boosting the immune response to Hepatitis C peptides and we believe that it could be refined for many different viral infections and cancers. We have also shown it can be used to induce immune responses against drug resistant forms of HIV. The OPAL technique is simpler than current cell-based vaccine techniques which usually require isolation of rare specialised cells from blood.”
Human studies are expected within two years.