Island Scientists Probing Clone for Infection Clues
By Lora-Marie Bernard
AS THE COUNTY wrestles with seven confirmed cases of zika infection, a Galveston Island research team is experimenting on a clone of the virus in an effort to find a vaccine to fight its effects on humans.
The University Of Texas Medical Branch team’s manmade virus – developed in spring – has a DNA copy of the actual virus and the researchers are able to manipulate its genetic fingerprint at will in a tube or petri dish. They are hoping to discover the process by which the mosquito-borne virus enters the womb and causes such abnormalities as microcephaly, which severely damages fetuses’ brains and prevents normal growth of their heads.
Pei-Yong Shi, who works on the team, described UTMB’s genetically-engineered version as “one of the most powerful virology tools to study the virus” and said it “will answer and unravel a lot of mechanisms of how and why the virus became explosive”. Shi said the UTMB scientists are using the clone to study the virus’ ability to penetrate a pregnant woman’s placenta. Because they can test different parts of the manmade virus, they can try to isolate the element of the natural virus that could be giving it the ability to enter the womb. The confirmed Galveston County cases have included women who were traveling overseas when they contracted the mosquito-borne illness but the county district does not reveal personal details such as pregnancy when recording the cases.
Shi, who, before joining the UTMB zika initiative in 2015, led a New York community response team that developed a clone for the West Nile Virus, said the Zika Virus has been in existence for 70 years but remained obscure with few identified human cases until about a decade ago. “For the first 60 years after its discovery, it really didn’t cause too many diseases,” he said, adding that people who were infected at that time showed only mild symptoms. That changed in 2007 when the virus sparked frequent epidemics associated with known serious diseases. Among them were microcephaly and Guillain-Barre syndrome, he said.
“It also causes millions of infections in, for example, Brazil,” he added. UTMB scientists became interested in understanding the surge and developed hypothesizes to explain it. Their cloned virus will help the team test the hypothesizes. “For example, the virus might have changed in the past 10 years,” Shi said. “That change might cause an increased ability of the virus to be transmitted by mosquitoes. If the virus has changed and that change increases its efficiency in mosquito transmission, then there will be more spread.”
The clone also allows scientists to study the virus’ changing fingerprint, enabling them to test to see if previous stages of the virus were “less transmissible” than the latest version. “Basically, using this system, we can make a panel of viruses at our will and recapitulate the history of the virus,” Shi said. “You can make 1950, 1960, 1970, 1980. You can make an evolution.”
Despite its strength, calling Zika a “super virus” is a relative term, he said. “I think the virus just keeps evolving in a different ecosystem and we just have to cope with it.” Referring to the cloning project, he said: “I feel confident that, if there is anything we can contribute very rapidly, this is one of them.”
Shi’s team wrote about its cloning project in the May edition of the medical publication Cell Host and Microbe.