A method for developing antibodies with the ability to kill multiple strains
of the human
immunodeficiency virus (HIV) was announced by South African scientists
working with US researchers.
A small number of HIV-infected
people developed the antibodies, but are not helped by them because they are
unable to kill the wide range of HIV, said National Institute of Communicable
Diseases virology head Prof Lynn Morris.
Broadly neutralising antibodies
"We need to understand how to make better antibodies
to HIV. We can learn that from people who are already infected, because a small
proportion of them [infected people] make these broadly neutralising
antibodies," she told reporters in Johannesburg.
"There has been a lot of focus on the individuals that make this
special type of antibodies. That information, we hope, is going to help us make
a better vaccine to HIV."
A KwaZulu-Natal woman, identified in the research as CAP256, had responded
to HIV infection by making the broadly neutralising antibodies.
The research team had identified these antibodies in her blood and
duplicated them by cloning them in a laboratory.
A new vaccine
The cloned antibodies were then used in a series of experiments to clarify
the pathway followed by CAP256's immune system to make the HIV-combating
The identification and successful cloning of the antibodies had enabled
researchers to make large quantities for further testing, similar to the way a
medicine used to prevent or treat HIV would be tested.
"What we have to do now is to design a vaccine that is able to engage
with the rare B-cells. If we are able to do that, we should be able to make a
vaccine that will take months for people to develop the immunity against
HIV," said Morris.
kill 88% of HIV types
Sometimes referred to as the body's army, antibodies are specialised cells
produced by B-cells as a primary immune defence. They are used by the body for
either treatment or prevention.
Morris said CAP256's antibodies would be used in a sequence of pre-clinical
trials in monkeys, a process which could take years to prove their efficacy.
US vaccine research centre
If successful, the research would guide HIV vaccine development. The
antibodies might also be used as treatment for HIV.
The research was primarily funded by the US vaccine research centre, and the
science and technology department.
The scientists worked in the "Caprisa" consortium of Aids
researchers, which included the University of KwaZulu-Natal, the University of
the Witwatersrand, the National Institute of Communicable Diseases, the
University of Cape Town, and Columbia University in the US.
lauds HIV discovery
of antibodies could control HIV
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