Of sorts - they've got one that works correctly for mice, but a vaccine for a feline coronavirus (I think the disease is FIP, and I remember my cats getting the nasal vaccine for a couple of years) was later found to worsen the disease.
http://my.webmd.com/content/Article/84/98316.htm?printing=true "...Nabel's team has developed a DNA vaccine that carries a SARS gene. The gene encodes one of the surface molecules on the SARS virus. In a major breakthrough, they now report that three doses of this vaccine fill mice with anti-SARS antibodies. After having SARS virus sprayed into their noses, the vaccinated mice get a million times less virus in their lungs than unvaccinated mice. "DNA vaccination with the [SARS gene] results in protective immunity," Nabel and colleagues write in the April 1 issue of Nature." "The SARS virus is a coronavirus. There's never been a human coronavirus vaccine. Attempts to vaccinate cats against a deadly feline coronavirus ended up making the disease worse, not better. This didn't happen in mice that got the SARS DNA vaccine. But nobody knows what will happen in people. "Nabel and colleagues say that human tests are needed -- not only to find out if the vaccine is safe, but to find out how well it works. And that's complicated, because DNA vaccines are very new. Only a few experimental DNA vaccines have ever been tested in humans. None has yet been shown to protect against human disease, although most researchers consider this to be simply a matter of time. "It will be necessary to test potential SARS vaccine candidates for their immunogenicity, safety, and efficacy in humans in the event of future outbreaks," Nabel and colleagues write." The possibilities for such DNA-containing vaccines are intriguing, but I can see why there are confounding factors; for one, if you're vaccinating against a gene instead of the gene product (e.g. a protein), then that means the body must see the _contents_ of the viral or bacterial particle/cell, not just the coating/cell wall. So that gene must either be expressed on the surface of the infected body cell, or some of the particles/invading cells must be broken down, and enough of the gene in intracellular fluid provokes a sufficient immune response to kill the vast majority of infected body cells. {I wonder if that's what happened to the cats -- such a strong response was generated that too much normal tissue got killed.} Debbi No Civit Cats On My Menu, Please Maru __________________________________ Do you Yahoo!? Yahoo! Small Business $15K Web Design Giveaway http://promotions.yahoo.com/design_giveaway/ _______________________________________________ http://www.mccmedia.com/mailman/listinfo/brin-l
