Victorian researchers have made a significant step in understanding how the virus works. By Amie Larter.
A team of researchers from Melbourne's Alfred Hospital, Monash University and the Burnett Institute have made a key discovery in the fight against HIV, unlocking one of the disease's major mysteries.
According to Sharon Lewin, director of the Infectious Disease Unit at Alfred Hospital, when people are on anti-HIV drugs, the virus will effectively "go to sleep" inside resting cells.
This has meant that one of the major barriers in HIV research is finding out how the resting cells are infected and why the cells remain hidden - despite long-term treatment.
The team found that common anti-cancer chemotherapy drug vorinostat, part of the family of drugs known as histone deacetylase inhibitors (HDIs), effectively 'woke up' the virus.
"All HIV patients need is to take anti-HIV drugs and that keeps the virus under control, and what we were trying to do with the cancer drug is to dig out those last bits of the virus that hang around in people on the anti-HIV drugs.
"It [vorinostat] actually turned the virus back on - but it only wakes the virus from a particular kind of cell where the virus is hiding," Lewin said.
Twenty healthy people who all had HIV and were taking anti-HIV drugs received fourteen days of vorinostat as part of the research.
Lewin told Nursing Review that the hope of the research is that once the virus is awakened and starts producing copies of itself, that the infected cell would become visible to the immune system or might even die.
"We haven't demonstrated that that happens - the first step is just showing that we can wake the virus up. We are still a long way off getting rid of the sleeping cells but it has given us a clue that we can actually wake them up."
Vorinostat was the first of the HDI family to be licensed, and Lewin said that future studies may involve a combination of other drugs in the group.
"There are other HDIs that are probably more potent than vorinostat so [the research] has given us a much better understanding of how to dose and give these drugs to inform future studies of the newer inhibitors.
"The next studies may need combination treatment - activating the virus in multiple ways and finally the other approach is to activate and try and kill the cell."
The team plans to continue monitoring the twenty patients who have already received the drug to better understand the changes the drug made to the virus and each patient's genes.
"We think there are a lot more questions to answer, and we are doing that in a few different ways.
"We are looking at the sequence - the genetic code of the virus that comes out of these cells - because that might tell us more about where it is coming from.
"We are also looking at the host response to the drugs - following these patients up now for a lot longer to see what happens to the virus once it's been woken up," Lewin said.
Australia had 31,645 cases of HIV diagnosed by the end of 2011, according to the 2012 Annual Surveillance Report of HIV, viral hepatitis and STIs.Do you have an idea for a story?
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