Scientists think they've developed the ultimate killer. But don't worry. It's on your side.
It's name is DRACO and it could be the next all-inclusive virus killing drug. Scientists at MIT are in the process of developing a drug that identifies and kills cells that have been invaded by a virus, while leaving healthy cells alone.
Tested against 15 different viruses, the drug proved effective against all of them. First, the drug identifies virus-infected cells by targeting a molecule common in all of them. New Scientist reports:
Nearly every virus generates strings of double-stranded RNA longer than 30 base pairs during transcription and replication, in an attempt to duplicate itself and commandeer its host cell's machinery. Healthy mammalian cells do not produce double-stranded RNA longer than 23 base pairs.
The body's own immune system has an enzyme that searches for double-stranded RNA longer than 23 base pairs. When it finds them, it actives the infected cell's immune response. But some viruses have evolved to outsmart this enzyme.
What Tom Rider and his team at MIT's Lincoln Laboratory did to catch these viruses was pair the aforementioned enzyme that finds abnormal RNA with a protein that triggers cell death. New Scientist goes on:
The drug "catches the virus with its pants down", by destroying the cell before new viruses have been assembled inside it, explains Rider. Even if fragmented virus molecules escape the obliterated cell, they will be missing the protein coat that helps them to travel between cells, and so will not infect surrounding healthy tissue. Rider calls his drug double-stranded RNA (dsRNA)-activated caspase oligomeriser (DRACO).
According to an MIT press release, the scientists initially did testing on human and animal cells, but did use the drug in mice infected with H1N1 as well. The drug cured the mice and left them unharmed. The scientists are moving forward with researching its success on other viruses in mice.
Although results look promising, New Scientists include a couple different perspectives that could pose problems for DRACO in the future.
Andrea Branch of the Mount Sinai School of Medicine in New York City thinks the work is intriguing but has some reservations about its practicality. She points out that DRACO is a large protein, which may not enter cells easily.
That said, she agrees that administering DRACO early in an infection could be effective – but adds that destroying all cells infected with the virus can be dangerous in people with advanced viral infections. "Suppose 100 percent of your hepatocytes [liver cells] are infected and you used this – you would die of liver failure."
Timothy Tellinghuisen of the Scripps Research Institute in Jupiter, Florida, adds that some viruses have evolved ways to conceal their double-stranded RNA, and so could elude DRACO. Still, "this is really an interesting paper, a very clever approach to getting rid of cells containing double-stranded RNA", he says.
The results of this study are published in Plos One. Rider, the lead scientist for this study is also know for inventing PANACEA, another antivirual therapeutic, and CANARY (Cellular Analysis and Notification of Agtigen Risks and Yields), a sensor for rapid pathogen detection and identification.