Tobacco-derived drug prevents cavities
uses transgenic tobacco plants to cultivate the human protein
CaroRx, which could prevent tooth decay in the future.
The cultivation of these plants for eventual use in the pharmaceutical industry is set to become a subject of much focus, as attention is not concentrated on the risks of green biotechnology, but rather on its medicinal possibilities.
The concept of fighting diseases using biologically active proteins is an established approach, adopted by many biotechnology companies such as Genentech or Chiron. These companies are currently conducting research into rheumatism or multiple sclerosis using transgenic microorganisms or mammalian cells, rather than tobacco plants.
The company, Planet Biotechnology, in collaboration with scientists from the University of Aachen, St. George Hospital London and the Fraunhofer Institute for molecular biology and applied ecology, worked together to identify CaroRx as the first active substance to be clinically tested on patients with success in the absence of side effects.
Tooth decay is a problem that has seen a comeback in recent years, particularly in the industrialised world amongst children. The increase in sugary snacks and drinks has been attributed to the cause of this increase.
Cavities are caused by a bacterium, called Streptococcus mutans, which has a mechanism of action that sticks to enamel proteins with the use of small protein antennas. These proteins process food sugars into milk acid, which attacks the enamel.
The study results for the anti-cavity tobacco plant agent are nevertheless promising. Dentistry students who applied it at the beginning of the study were cavity-free for one year. For it to be allowed on the market, it will need to prove effective in a phase 3 study with a larger number of patients.
Eva Stoeger, researcher at the University of Aachen said that the CaroRx recognised these attennas, blocking them, making them "impossible for bacteria to dock onto the tooth."
However, critics point to the ongoing problem that occurs with certain microorganisms. Bacteria have been known to deliver the proteins in useless clumps. In addition, mammalian cells need to be tested for pathogens that could possible infect humans.
"It's important to optimise the technical filtering of the proteins from the plants," said Eva Stoeger. "Guidelines for production will have to be developed, that would have to be valid for traditional pharmaceutical companies, as well. If these obstacles are overcome, plants will turn out to be promising, safe and economical bio-factories," said Stoeger.
This attitude is greeted with doubt by biotechnology experts in Germany. Indeed, the suspicion toward genetically modified plants is widespread in Europe. It was only a short while ago that the German government passed a law regarding genetic engineering.
Many biotechnologists think this law is an effort to stifle their research, as it allows institutes and farmers who sow genetically manipulated seeds to be sued if a neighbouring field is contaminated by windborne transgenic pollen by more than 0,9 per cent-for most, an incalculable risk.
At the same time, the European Union is supporting a new project to develop vaccines against rabies, tuberculosis, diabetes and HIV from plants. The first tests with these medications are expected in 2009.
