Tobacco plants might yield a cheap and easy-to-administer vaccine against a pesky stomach virus called norovirus, US researchers said recently. They found a way to make tobacco produce a protein that can be used to make a nasal vaccine against norovirus, which causes diarrhea and vomiting, especially on cruise ships, in restaurants, schools and on military bases. The US Centres for Disease Control and Prevention estimates that 23 million cases a year of acute gastroenteritis are due to norovirus, also known as Norwalk virus. Researchers at Arizona State University used a genetically engineered plant virus called the tobacco mosaic virus to start their vaccine. ?We call them nanoparticle vaccines because the protein we produce in our tobacco plant self-assembles into a little round ball,? the researchers said. The immune system recognises this ball, called a virus-like particle or a capsid, as if it were a virus and attacks it. Tests have suggested the vaccine would work better in the nose than taken orally, probably because immune cells in the nasal passages are more inclined to take up the vaccine. Norovirus sticks to surfaces well and can live a long time unless thoroughly cleaned off. The technology could be applied to other vaccines as companies race to make vaccines against the new pandemic H1N1 swine flu virus.
Faking evidence
Scientists in Israel have demonstrated that it is possible to fabricate DNA evidence, undermining the credibility of what has been considered the gold standard of proof in criminal cases. The scientists fabricated blood and saliva samples containing DNA from a person other than the donor of the blood and saliva. They also showed that if they had access to a DNA profile in a database, they could construct a sample of DNA to match that profile without obtaining any tissue from that person. The planting of fabricated DNA evidence at a crime scene is only one implication of the findings. A potential invasion of personal privacy is another. Using some of the same techniques, it may be possible to scavenge anyone?s DNA from a discarded drinking cup or cigarette butt and turn it into a saliva sample that could be submitted to a genetic testing company that measures ancestry or the risk of getting various diseases. The scientists fabricated DNA samples two ways. One required a real, if tiny, DNA sample, perhaps from a strand of hair or drinking cup. The other technique relied on DNA profiles, stored in law enforcement databases as a series of numbers and letters corresponding to variations at 13 spots in a person?s genome.
Bio chip
IBM is looking to the building blocks of our bodies?DNA?to be the structure of next-generation microchips used in computers, cellphones and other electronic devices. As chipmakers compete to develop ever-smaller chips at cheaper prices, designers are struggling to cut costs. Artificial DNA nanostructures, or ?DNA origami? may provide a cheap framework on which to build tiny microchips. Recently, IBM gave the first demonstration of using biological molecules to help with processing in the semiconductor industry. The research was a joint undertaking by scientists at IBM?s Almaden Research Centre and the California Institute of Technology. Researchers said that if the DNA origami process scales to production-level, manufacturers could trade hundreds of millions of dollars in complex tools for less than a million dollars of polymers, DNA solutions, and heating implements. But the new processes are at least 10 years out.