August 11, 2011

Drug Could One Day Cure Virtually Any Viral Infection

Researchers have developed technology that may one day be the cure for nearly any viral infection.

Researchers at MIT's Lincoln Laboratory designed a drug that can identify cells that have been infected by any type of virus, which then kills those cells to terminate the infection.

The team found that their drug was effective against all 15 viruses they tested it on, including viruses that cause the common cold, H1N1 influenza, a stomach virus, a polio virus and several other types of hemorrhagic fever.

The drug works by targeting a type of RNA produce only in cells that have been infected by viruses.

"In theory, it should work against all viruses," Todd Rider, a senior staff scientist in Lincoln Laboratory's Chemical, Biological, and Nanoscale Technologies Group who invented the new technology, said in a press release.

Other members of the research team are Lincoln Lab staff members Scott Wick, Christina Zook, Tara Boettcher, Jennifer Pancoast and Benjamin Zusman.

Rider got the idea of developing a broad-spectrum antiviral therapy after inventing Cellular Analysis and Notification of Antigen Risks and Yields (CANARY), which is a biosensor that can rapidly identify pathogens.

"If you detect a pathogenic bacterium in the environment, there is probably an antibiotic that could be used to treat someone exposed to that, but I realized there are very few treatments out there for viruses," he said in a press release.

According to MIT, Rider drew inspiration for his therapeutic agents known as DRACOs, or Double-stranded RNA Activated Caspase Oligomerizers.

The viruses during this process create long strings of double-stranded RNA (dsRNA).  Human cells have proteins that latch onto dsRNA, which sets off a cascade of reactions that prevents the virus from replicating itself.

Many viruses are able to outsmart that system by blocking one of the steps further down the cascade.

Rider had the idea of combining a dsRNA-binding protein with another protein that induces cells to undergo apoptosis.

Karla Kirkegaard, professor of microbiology and immunology at Stanford University, said combining those two elements is a "great idea" and a novel approach. 

"Viruses are pretty good at developing resistance to things we try against them, but in this case, it's hard to think of a simple pathway to drug resistance," she said in a press release.

The researchers are now testing DRACO against more viruses in mice and are finding promising results.

Rider said he hopes to license the technology for trials in larger animals and for eventual human clinical trials.

The researchers published their study in the journal PLoS ONE on July 27.


Image Caption: The microscope images above show that DRACO successfully treats viral infections. In the left set of four photos, rhinovirus (the common cold virus) kills untreated human cells (lower left), whereas DRACO has no toxicity in uninfected cells (upper right) and cures an infected cell population (lower right). Similarly, in the right set of four photos, dengue hemorrhagic fever virus kills untreated monkey cells (lower left), whereas DRACO has no toxicity in uninfected cells (upper right) and cures an infected cell population (lower right). Credit: MIT/Lincoln Lab


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