British Scientists Develop
Vaccine Against Tooth Decay
Discovery News Brief

LONDON (Reuters) - British scientists said Tuesday they had developed a safe, effective and painless vaccine to prevent tooth decay.
It is a plant-based vaccine that is painted on teeth and produces antibodies that prevent harmful bacteria from sticking to teeth and causing cavities. ``This will be a significant step to reducing tooth decay,'' Dr. Julian Ma, one of the scientists, said in an telephone interview Tuesday.
Ma and Professor Tom Lehner led the team of researchers at Guys Hospital dental school in London that produced the vaccine by genetically modifying tobacco plants to carry antibodies to Streptococcus mutans, which causes 95 percent of tooth decay. The tasteless, colorless vaccine was successfully tested on people during a four-month trial. Volunteers received it twice a week for three weeks for a total of six applications. ``What we showed is that by applying this antibody you can prevent the bacteria that is targeted against -- Streptococcus mutans -- from sticking to the teeth,'' Ma added.
In the trial, reported in the May issue of Nature Medicine, the researchers used a mouth rinse to reduce the levels of the bacteria in the volunteers to zero. Then they applied a control, or placebo solution, to some patients and the vaccine to others. Within two months, the bacteria returned in the mouths of the control group while those who received the vaccine were protected for up to four months.
``This is the first plant-derived vaccine from genetically modified plants to ever go into human clinical trials,'' said Ma.
``We have now found a way of using plants to produce this vaccine safely and in large quantities. It would not be possible otherwise,'' he said
The type of antibody the vaccine makes is similar to what the human body produces in the immune system to protect against infections. The scientists are really boosting the body's immune system by giving it extra antibodies. ``Ninety percent of human infections start at mucosal surfaces, like the throat, lungs and gut. With this technique we could make other antibodies in plants to prevent these infections,'' Ma added.
``The basic principle is topical application of antibodies.'' Planet Biotechnology, a California-based company that is developing the technology with Guy's Hospital, are planning larger clinical trials this summer.

Sightings HomePage