- News Home
5 December 2013 11:26 am ,
Vol. 342 ,
Researchers have been hot on the trail of the elusive Denisovans, a type of ancient human known only by their DNA and...
Thousands of scientists in the Russian Academy of Sciences (RAS) are about to lose their jobs as a result of the...
Dyslexia, a learning disability that hinders reading, hasn't been associated with deficits in vision, hearing, or...
Exotic, elusive, and dangerous, snakes have fascinated humankind for millennia. They can be hard to find, yet their...
Researchers have sequenced and analyzed the first two snake genomes, which represent two evolutionary extremes. The...
Snake venoms are remarkably complex mixtures that can stun or kill prey within minutes. But more and more researchers...
At age 30, Dutch biologist Freek Vonk has built up a respectable career as a snake scientist. But in his home country,...
Since arriving on the island of Guam in the 1940s, the brown tree snake ( Boiga irregularis ) has extirpated native...
- 5 December 2013 11:26 am , Vol. 342 , #6163
- About Us
A Vaccine Stronger Than the Stomach
14 November 1997 8:00 pm
Researchers have developed the first oral vaccine against botulism, a bacterial infection that can lead to paralysis and death. The advance, reported in this month's Infection and Immunity, could someday be adapted to make oral vaccines against other diseases, such as diphtheria or tetanus, that plague some developing countries.
While oral vaccines are easier to deliver to patients than injections, it's hard to develop them because most potential vaccines are destroyed by stomach acid. Lance Simpson, a medical professor at Jefferson Medical College in Philadelphia, thought botulism toxin might be an ideal candidate for an oral vaccine. Unlike most proteins, botulism toxin from spoiled canned food, for instance, survives the stomach on its way to its target: nerve cells that control muscles. Once at the nerve endings, the toxin breaks down syntaxin, a protein that directs the release of neurotransmitters. Mice infected with botulism die within 2 hours, and people often die from the infection also.
To detoxify botulism toxin, Simpson mutated the region of the protein that disrupts nerve function, leaving the remainder intact. When he fed the altered protein to mice, they developed antibodies--against both the mutated and natural versions of botulism toxin--that protected the animals from the bug. The vaccine did not harm cultured mouse nerve cells.
Although there is an injected botulism vaccine now in clinical trials, Simpson says his oral vaccine would be easier to administer in developing countries and could also be fed to racehorses and waterfowl species that are prone to botulism (Science, 7 November, p. 1019). The botulism toxin might even become a vehicle for delivering other vaccines, Simpson says: "If we can get botulism toxin through the immune system, maybe we can put other proteins on there and create a whole group of oral vaccines."