Some of the most common and deadly viruses to humans are RNA based and have little in the way of FDA approved treatments.
To address that, a team of researchers led by the Broad Institute of MIT and Harvard developed an antiviral agent that can find and destroy RNA-based viruses hiding out in human cells.
There's a lack of drugs to kill these RNA viruses
In a research report, which was published in journal Molecular Cell, the researchers co-led by senior author Pardis Sabeti, a member at the Broad Institute and a professor at Harvard University, Catherine Freije, a graduate student at Harvard University, and Cameron Myhrvold, a Graduate School of Arts and Sciences postdoc, were able to turn a CRISPR RNA cutting enzyme into an agent that can destroy the viruses including Ebola, Zika and flu.
The efforts on the part of the researchers comes at a time when drugs aren't doing enough to kill these infections. According to the researchers, during the past 50 years, 90 clinically approved antiviral drugs have been developed but they only treat nine diseases. The drugs don't reflect the fact that viral pathogens can evolve and become resistant to current treatments. The researchers noted that only 16 viruses have vaccines that are approved by the FDA.
CARVER systems could fight a variety of viruses
The researchers had previously made the Cas13 enzyme into a tool to cut and edit RNA and to detect viruses and bacteria in human cells. Now they are using Cas13 or any CRISPR system to act as an antiviral in human cells. The researchers combined the capabilities of Cas13 into one system that in the future could diagnose and treat these infections. The system is Called CARVER.
“Human viral pathogens are extremely diverse and constantly adapting to their environment, even within a single species of virus, which underscores both the challenge and need for flexible antiviral platforms,” said Sabeti, who is also a Howard Hughes Medical Institute investigator said in a press release highlighting the research. “Our work establishes CARVER as a powerful and rapidly programmable diagnostic and antiviral technology for a wide variety of these viruses.”
Researchers' tool reduced the viral RNA cells 40 fold
To test the effectiveness of its CARVER system, the researchers tested it in human cells that had lymphocytic choriomeningitis virus (LCMV), influenza A virus (IAV), and vesicular stomatitis virus (VSV). Twenty-four hours after introducing the Cas13 gene and a guide RNA into the cells, the researchers exposed the cells to the virus. After another 24 hours, the Cas13 enzymes reduced the level of viral RNA in the cells by as much as 40 times.
“We envision Cas13 as a research tool to explore many aspects of viral biology in human cells,” said Freije in the same press release. “It could also potentially be a clinical tool, where these systems could be used to diagnose a sample, treat a viral infection, and measure the effectiveness of the treatment — all with the ability to adapt CARVER quickly to deal with new or drug-resistant viruses as they emerge.”