makes AIDS breakthrough
New York, January 18, 2006
'Friendly bacteria' found in yoghurt has been
genetically modified by a team of US researchers
headed by an Indian American to produce a drug
that blocks HIV infection.
Although the bacteria has only been tested
in a lab dish, scientists are optimistic the
technique could provide a cheaper and more effective
way of delivering drugs to fight the spread
of AIDS, by getting the bugs to live right where
the drugs are needed most, Nature magazine reported.
The bacterium (Lactococcus lactis) the researchers
have modified naturally produces lactic acid,
and so is used to produce cheese and yoghurt.
It is also found in some parts of the human
anatomy, including the gut and the vagina, where
the acid it produces damps down the growth of
other, harmful bacteria, Nature said.
Some 'probiotic' yoghurts are loaded with such
beasties with the aim of keeping consumers'
guts healthy. Bharat Ramratnam, an HIV specialist
at Brown Medical School, Providence, Rhode Island,
and his colleagues have now altered the genetic
make-up of L.lactis so that it generates cyanovirin,
a drug that has prevented HIV infection in monkeys
and human cells, and is on track for human trials
in 2007, the magazine reported.
ANI adds: Cyanovirin binds to sugar molecules
attached to the HIV virus, blocking a receptor
that HIV uses to infect cells.
"It's basically passive immunization,"
says Sean Hanniffy, a molecular biologist at
the Institute of Food Research, Norwich, UK,
and part of the team.Gels containing cyanovirin
could afford some protection for women against
the transmission of HIV, but since the drug
breaks down quickly these would have to be used
just before sex. "In some countries there's
a reluctance to use these gels frequently,"
Because lactic-acid bacteria live naturally
in the vagina, one application of a bacterial
goop should see the modified bugs thrive there
for at least a week, says Hanniffy. "The
next step might be to use other bacteria that
can survive for even longer," he adds.