While the tobacco used in cigarettes poses major health hazards, scientists have found a way to use the commercial tobacco plant to generate positive outcomes.
Local scientists at the CSIR have collaborated with the National Institute of Communicable Diseases and Mapp Biopharmaceuticals to develop a bio-manufacturing process where DNA codes are injected into six-week-old tobacco plants grown from seedlings, that allows the plant to produce antibodies that can be used to improve the quality of life of HIV-positive patients.
“We introduce the DNA (into the tobacco plant leaves) that encodes these antibodies to them and allows them to process it and produce the antibodies,” CSIR scientist Dr Tsepo Tsekoa told Business Report.
The plant is then left for six days to process the DNA before the juices are harvested in the lab and blended.
“(The leaves) produce a green juice from which we extract the proteins we want,” he explains. The proteins are then purified and tested.
Tests conducted thus far show that plant-expressed antibodies are able to neutralise various strains of HIV in the lab.
Previously, researchers from the Centre for Aids Programme of Research in SA (Caprisa) were able to produce antibodies through the use of a mammalian-based cell culture system and now CSIR scientists have managed to replicate these antibodies using the Nicotiana benthmiana – a relative of the commercial tobacco plant.
The implications of this breakthrough, says Tsekoa, is that plant-expressed antibodies can now be produced on a large scale, making access to and affordability of antibodies more viable for South Africans.
“We test them on cells we produce and so far that method has proven successful. The main angle is to make it cheaper than what is currently available and eventually roll out a massive production so that everyone can have it,” he was quoted saying.
For now, the scientists will be focused on developing potential products like gels or other forms of pre-exposure prophylaxis against HIV that can be tested on humans.
“Although an effective vaccine against HIV is yet to be discovered, the past 32 years of the epidemic have seen some important developments that are leading us towards the discovery of an effective HIV vaccine. There are high hopes that the world is getting to zero,” Tsekoa says.
Source: Business Report