A team of researchers led by King's College London has for the
first time identified a new gene which may have the ability to
prevent HIV, the virus that causes AIDS, from spreading after it
enters the body.
The study is the first to identify a role for the human MX2 gene
in inhibiting HIV. Researchers say this gene could be a new target
for effective, less toxic treatments where the body's own natural
defence system is mobilised against the virus.
Scientists carried out experiments on human cells in the lab,
introducing the virus to two different cell lines and observing the
effects. In one cell line the MX2 gene was expressed or
'switched on', and in the other it was not, or 'silenced'. They saw
that in the cells where MX2 was silenced, the virus replicated and
spread. In the cells where the MX2 gene was expressed, the virus
was not able to replicate and new viruses were not produced.
The work was led by Dr Caroline Goujon and Professor Mike Malim
at the Department of Infectious Diseases, King's College London.
Professor Malim said: "This is an extremely exciting finding which
advances our understanding of how HIV virus interacts with the
immune system and opens up opportunities to develop new therapies
to treat the disease. Until now we knew very little about the MX2
gene, but now we recognise both its potent anti-viral function and
a key point of vulnerability in the life cycle of HIV.
"Developing drugs to stimulate the body's natural inhibitors is
a very important approach because you are triggering a natural
process and therefore won't have the problem of drug resistance.
There are two possible routes - it may be possible to develop
either a molecule that mimics the role of MX2 or a drug which
activates the gene's natural capabilities.
"Although people with HIV are living longer, healthier lives
with the virus thanks to current effective treatments, they can
often be toxic for the body and drug resistance can become an issue
with long-term use. It is important to continue to find new ways of
mobilising the body's natural defence systems and this gene appears
to be a key player in establishing viral control in people with
HIV."
The paper, Human MX2 is an interferon-induced post-entry inhibitor of HIV-1
infection, is published in Nature.