TUESDAY, SEPTEMBER 27, 2016

Scientists discover method to make lung cells fight off H5N1 virus

Researchers from the Icahn School of Medicine at Mount Sinai recently discovered a way to keep highly infectious diseases from infecting researchers by using a molecular biocontainment method that causes lung cells to attack flu, or other RNA, viruses.

The study, led by Mount Sinai Microbiology and Medicine professors Dr. Adolfo Garcia Sastre and Dr. Benjamin tenOever, was published in a recent issue of Nature Biotechnology. The research came after a ban was placed on studying the H5N1 bird flu due to the risk it posed to infecting researchers and potentially causing a global outbreak.

"The question last year was whether the risk of altered bird flu escaping laboratories justified the science aimed at understanding the transmission of these viruses," tenOever said. "With our method, the possibility of human transmission is no longer a concern."

The new discovery protects researchers from all influenza A viruses, which include both H5N1 and H7N9, and will also potentially protect against other RNA viruses like SARS. TenOever based his research on a plant model. Plants use small RNA molecules to fight off foreign viruses, so the researchers tried to use the same process in ferrets and mice.

"When a plant recognizes viral material, it creates a small inhibitory RNA, called siRNA, that latches on to the virus and cleaves it," tenOever said.

Humans also have small RNA molecules, called miRNA, that maintain cell health in the human body. Garcia-Sastre, tenOever and a team of scientists from the University of Maryland's Department of Veterinary Medicine found a way to change the viral genome of the miRNA cells into a defensive cell just like that of a plant.

The approach uses the miRNA in human lungs and changes them into RNA virus fighting cells, protecting researchers from the possibility of being infected by H5N1, a virus that kills more than 50 percent of the people it infects. The process can, however, likely be applied to any area of the body to protect against a multitude of infections.

"It is clear that we can apply this technology to any virus," tenOever said. "The only requirements are that we need a miRNA that is present in humans, but not in the model system where we want to study the virus, such as in ferrets. We also need a viral genome that permits insertion of miRNA target sites."