South African study 'opens new possibilities for curing HIV'

A group of South African scientists,
working with scientists from the US, has
discovered how a KwaZulu-Natal
woman's body responded to her HIV
infection by making potent antibodies -
called broadly neutralising antibodies -
that could open up new ways of treating
and preventing HIV. Details of the
discovery of the antibodies -
Details of the discovery of the
antibodies -called broadly neutralising
antibodies because they are able to kill
multiple strains of HIV from across the
world -was published in the prestigious
scientific journal Nature on Sunday.
The
study describes how the research team
found and identified these antibodies in
a KwaZulu-Natal woman's blood and
then duplicated them by cloning the
antibodies in the laboratory.
The cloned antibodies were then used
in a series of experiments to elucidate
the pathway followed by the woman's
immune system to make these potent
antibodies. The study was conducted by
South African researchers in the Caprisa
(Centre for the Aids Programme of
Research in South Africa) consortium,
working jointly with US partners based
at the Vaccine Research Center of the
National Institute of Allergy and
Infectious Diseases, part of the National
Institutes of Health, and Columbia
University in New York. Caprisa includes
scientists from the National Institute for
Communicable Diseases in
Johannesburg, the University of
KwaZulu-Natal and the University of
Cape Town.
'Hope for future prevention, treatment
strategies'
Professor Salim Abdool Karim, leader of
the Caprisa consortium, said in a
statement on Sunday that the new
insights gained from the study into
immune responses against HIV "bring
hope for future HIV prevention and
treatment strategies", adding that the
woman whose antibodies were studied
"is doing well on antiretroviral therapy
and continues to attend the Caprisa
clinic regularly".
Just over a year ago, the same team of
South African researchers reported in
Nature Medicine (also part of the Nature
group of journals) on their discovery
relating to two other KwaZulu-Natal
women, that a shift in the position of
one sugar molecule on the surface of
the HIV virus led to the development of
broadly neutralising antibodies against
HIV. Professor Lynn Morris, who leads
the research team at South Africa's
National Institute for Communicable
Diseases (NICD), commented: "In this
new publication we have been able to
isolate a broadly neutralising antibody
from this Caprisa volunteer and trace its
origins to understand exactly how it
arose. "This could lead to new HIV
vaccine strategies that are able to
stimulate the rare precursors of these
protective antibodies," Morris said.
Antibodies 'with long arms'
According to Caprisa, all HIV-infected
people respond to HIV by making
antibodies. While most people's
antibodies are not able to kill
(neutralise) a wide range of HIV, a few
infected people naturally make
antibodies that kill many different kinds
of HIV, in other words, broadly
neutralising antibodies. "Broadly
neutralising antibodies have some
unusual features," said Dr Penny Moore,
one of the lead South African scientists
on the study based at the NICD.
"The outer covering (envelope) of HIV
has a coating of sugars that prevents
antibodies from reaching the surface to
neutralise the virus. In this patient, we
found that her antibodies had 'long
arms', which enabled them to reach
through the sugar coat that protects
HIV." In their study, the researchers
found that these antibodies had "long
arms" right at the outset. "We
discovered that some HIV antibodies are
born with 'long arms', requiring less
time and fewer changes to become
effective in killing HIV," Moore said.
The identification and successful cloning
of these special antibodies has enabled
the researchers to make sufficiently
large quantities for further testing,
similar to the way a medicine used to
prevent or treat HIV would be tested.
"Our goal is to test these antibodies,
preferably in combination with other
broadly neutralising antibodies, directly
in patients with HIV infection or in
patients at or in patients at risk of
getting infected," said Karim. "But this
will take some time, as the team is
currently planning animal studies as a
first step.
Broadly neutralising antibodies have
previously been shown to be effective
in preventing and treating HIV infection
in animals, but this has never before
been shown in humans." The future
studies on animals and humans are
being supported by the Strategic Health
Innovation Partnerships, a unit of the
South African Medical Research Council,
with funding from the Department of
Science and Technology.
'Importance of international scientific
partnerships'
Science and Technology Minister Derek
Hanekom said in the Caprisa statement
that the study "highlights the
importance of international scientific
partnerships and the contributions of
South African researchers to world-class
medical science. We are proud of the
South African research team who
conducted this ground-breaking study,
and thank the US partners for their
collaboration and support."
Health Minister Aaron Motsoaledi,
announcing the new findings at a press
conference in Johannesburg on Monday,
said: "We are a step closer to the day
where we eventually have a viable
vaccine because of what has been
announced the new findings at a press
conference in Johannesburg on Monday,
said: "We are a step closer to the day
where we eventually have a viable
vaccine because of what has been
announced today.
"This announcement tells us a little
more about the HI virus," Motsoaledi
said, adding: "These studies illustrate
the importance of research and the
need for patience and dedication. "In
2009, when we unveiled our 10-point
programme, number 10 was research
and development, and we were worried
that research and development in South
Africa was taking long in the past
decades. But we are very proud that
almost every year something is being
announced by our scientists in that
direction."
Motsoaledi said his department had
more interest in this development than
anyone else in the world, as South
Africa has the largest burden of HIV
infections globally. He thanked those
people living with HIV who had willingly
participated in the study.
"Your selflessness has been helping the
world to better understand the HIV virus
so that we can prevent transmission and
find the cure." The research was
primarily funded by the US National
Institutes of Health's Vaccine Research
Center and the South African
Department of Science and Technology.
The South African researchers also have
fellowships from the Wellcome Trust,
theTrust, the Fogarty International
Center, the National Research
Foundation and the Poliomyelitis
Research Foundation.
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