'Cruise Ship Virus' Vaccine Stems From Tobacco
TUESDAY Aug. 18, 2009 -- Scientists have developed a vaccine for the common viral infection norovirus from a novel source: a tobacco plant.
The new vaccine was "manufactured" in a tobacco plant using a bioengineered plant virus.
This plant biotechnology opens the door to faster, more inexpensive ways to bring vaccines to the public quickly, especially in times when viruses mutate into unpredictable new strains, said Charles Arntzen, who reported on the vaccine at the American Chemical Society annual meeting, in Washingtopn, D.C.
"The recent outbreak of H1N1 influenza virus has once again reminded us of the ability of disease-causing agents to mutate into new and dangerous forms," Arntzen said.
He added that, "for a case like the H1N1 influenza virus, you want to be able to move very rapidly and introduce a commercial vaccine in the shortest possible time. We think we have a major advantage in using engineered plant viruses to scale up vaccine manufacture within weeks instead of months."
The new vaccine for norovirus is a step in that direction. Norovirus is a dreaded cause of diarrhea and vomiting that may be the second most common viral infection in the United States, behind the flu.
Norovirus is sometimes called the "cruise ship virus," because the microbe can spread quickly through passenger liners, schools, offices and military bases. Because noroviruses are always mutating, it is a moving target for vaccine developers.
So Arntzen's team designed a vaccine-manufacturing process quick enough to keep up with shape-shifting viruses.
"With plant-based vaccines, we can generate the first gram quantities of the drug and do clinical tests within eight to 10 weeks. We could easily scale that up for commercial use in a two to four month period," Arntzen said.
Plant-based vaccine production also offers cost advantages. Building greenhouses costs less than the sterilized facilities, manufacturing technology and stainless steel tanks required for the insect or mammalian cell cultures used in most traditional vaccines, he noted.
The U.S. Centers for Disease Control and Prevention has more information on norovirus here.
Posted: August 2009