ASU researchers granted $1.5M to seek West Nile virus vaccine

[SOurce: Ken Alltucker, The Arizona Republic] - Arizona State University scientists are testing whether tobacco plants can yield a vaccine or drug that blocks the West Nile virus from attacking a person's central nervous system.

Researchers at ASU's Biodesign Institute received a four-year, $1.5 million grant from the National Institute of Allergy and Infectious Diseases to study ways to halt the disease. There is no drug that counteracts the virus, which last year infected more than 3,500 people in the United States and resulted in 109 deaths. There were 94 West Nile virus cases reported in Arizona.

The virus is typically transmitted by a mosquito bite and can cause serious illnesses such as encephalitis, meningitis and even a poliolike paralysis. People with weakened immune systems or those 50 or older are most at risk for developing West Nile encephalitis, according to the Centers for Disease Control and Prevention. Qiang "Shawn" Chen and his research team are studying ways to deliver drugs directly to a person's brain to attack the virus.

Now, viruses such as West Nile can traverse the "blood-brain" filter that protects the organ, but drug treatments cannot. Chen's team, which includes scientists from ASU and Washington University in St. Louis, is attempting to develop plant-based antibodies that can cross this filter and attack the virus directly. A key part of the research is to create a system that cranks out these plant-based proteins. This allows a mass-production system of sorts that allows researchers to test many types of proteins in a rapid fashion. The goal is to find one that has the potential to break the blood-brain filter. The group will inject proteins into the tobacco plants and harvest the leaves for potential drugs. It takes just 10 days or so to harvest the modified plants.

"Shawn has come up with a clever way to cross into and protect the brain," said Charles Arntzen, director of Biodesign's Center for Infectious Diseases and Vaccinology. Chen, an assistant professor at ASU's Polytechnic campus' department of applied biological sciences, said research of mosquito-borne disease is a personal mission. His father died after contracting meningitis from a mosquito bite while on a university-sponsored retreat in a remote area of China.

The University of Arizona, too, is studying ways to combat the West Nile virus. However, the Tucson researchers are studying a method that may prevent bites altogether. Scientists at UA's Bio5 Institute envision a molecule that would instantly kill a disease-carrying mosquito when it bites a human. This one-bite-and-you're-out molecule could be sprayed on mosquitoes, theoretically preventing the spread of mosquito-spread diseases such as West Nile virus, malaria, yellow fever or Dengue fever.