Technology may lead to more efficient vaccines and genetic therapies
MADISON - A research team has perfected a method for creating designer influenza viruses, which can be tailor-made to solve mysteries about how flu strains mutate, spread and cause illness.
The development may also lead to more efficient influenza vaccines and safer gene therapies, says Yoshihiro Kawaoka, a University of Wisconsin-Madison virologist and author of the report in the Aug. 3 Proceedings of the National Academy of Sciences (PNAS).
"This technology should help us gain a greater biological understanding of influenza and improve our methods of disease control," says Kawaoka.
Scientists have tried for years to create influenza viruses in the laboratory, but the process is made difficult by of the complexity of the virus, Kawaoka says. The influenza genome has eight different segments of RNA, compared to only one in viruses such as rabies.
To accomplish the feat, the researchers used a basic ingredient in biotechnology called plasmids, which are independent segments of DNA capable of replicating on their own. Plasmids are commonly used in science to transport genetic material from one cell to another.
Kawaoka and his School of Veterinary Medicine research group introduced eight plasmids - one for each segment of flu RNA -- into a common line of cells used for research. They also introduced nine other plasmids into the cells that serve as building blocks for the proteins needed to make a complete influenza virus.
Although Kawaoka says they are not entirely sure why the system works so well, it is producing viruses in about one in every 1,000 cells. It's a 1,000-fold improvement over current methods, which only produce altered viruses but not entirely new ones.
This technology is exciting, Kawaoka says, because it allows
scientists to precisely manipulate influenza viruses by flipping
genetic switches and producing mutat
Contact: Yoshihiro Kawaoka
University of Wisconsin-Madison