A new drug is being developed that would reduce the bio-terrorism threat of the Venezuelan equine encephalitis virus.
Biomedical researchers at the University of Texas Medical Branch at Galveston (UTMB) have announced to start the initial step in the development of effective drug therapies against Venezuelan Equine Encephalitis (VEE) virus, which is a potential bio-terrorist weapon. They claim to have determined the specific structure of a protein that the virus requires for replication.
The virus was developed into a biological weapon during the Cold War by both the United States and the Soviet Union; this has further fuelled fears by experts on the potential of VEE to be developed as a weapon of bio-terrorism. Reports have also indicated sporadic outbreaks of the mosquito-borne VEE virus periodically ravage Central and South America, that had caused infections to tens of thousands of people and killing hundreds of thousands of horses, donkeys and mules.
VEE protease inhibitors would function much like the protease inhibitors taken by people infected with HIV, Watowich said, but since human and equine immune systems could quickly overwhelm VEE viruses that were unable to replicate, infections would be eliminated instead of merely controlled, and permanent use of the medication would be unnecessary. (Those infected would also acquire immunity to VEE, just as if they had been vaccinated with a weakened form of the virus.)
Potential therapeutic compounds could be available for pre-clinical studies within two years, according to Watowich, thanks to collaborations with powerful computer centers at the University of Texas at Austin and IBM that will be able to take the UTMB protease structure and sift through "libraries" of millions of molecules, looking for those with the right structural and chemical characteristics to keep the "scissors" from closing.
To produce a detailed enough structure to begin this drug search, lead author and Watowich lab postdoctoral fellow Andrew Russo used X-ray crystallography, in which X-rays are used to scan crystallized protein samples, working both with equipment at UTMB and the high power synchrotron radiation source at Louisiana State University's Center for Advanced Microstructures and Devices in Baton Rouge. "It took about a year of hard work by Andrew, but it was worth it," Watowich said. "In the future when we're dealing with one of these periodic VEE outbreaks or a bioterrorist attack, it will be a very good thing if we have an effective medicine in the cabinet ready to use."