"We were extraordinarily lucky to have that other virus in our sample, because without the cell death it caused, we never would have done the work that led us to Eilat," Nasar said. "Essentially, we found it by accident."
Eilat's inability to grow in animal cells even its genetic material cannot replicate in them makes it unique among alphaviruses, and it also makes it likely that the virus could be uniquely valuable to researchers who study alphaviruses and work to protect humans and domestic animals from them. For example, the UTMB researchers say, Eilat could be transformed into a vaccine against one of its dangerous relatives by making changes to the genes that produce its envelope proteins, which are exposed on virus particle surfaces and stimulate the critical parts of the immune response.
"We have taken the genes for the envelope proteins of very dangerous viruses like eastern equine encephalitis and used them to replace the genes for Eilat's structural proteins," Nasar said. "That gives us viruses that we can grow in insect cells that can't do anything in vertebrate cells at all, but still produce immunity against eastern equine encephalitis they can be used to vaccinate animals, and hopefully someday people."
A variety of Eilat-based "chimeric viruses" viruses made by combining genetic material from other viruses could be used to study the interactions between host cells and dangerous alphaviruses, leading to the development of antiviral drugs. The viruses could also serve as the basis for new diagnostic tools that could be deployed in an alphavirus outbreak. Because these chimeras, like Eilat, would not be able to infect vertebrates, such research could be done without the elaborate and often cumbersome containment precautions needed for working with pathogens like chikungunya, Ve
|Contact: Jim Kelly|
University of Texas Medical Branch at Galveston