New roles in infectious process for molecule that inhibits flu

Researchers at The Ohio State University have identified new roles for a protein long known to protect against severe flu infection – among them, raising the minimum number of viral particles needed to cause sickness. The protein also helps prevent unfamiliar viruses from mutating after they infect a new host, the study found – meaning its absence during an immune response could enable an animal virus spilled over to people to adapt rapidly to human hosts. 

Senior study author Jacob Yount, PhD, professor of microbial infection and immunity in The Ohio State University College of Medicine, says the combined findings add up to potential trouble for people deficient in the protein, called IFITM3 – especially if an avian or swine flu were to gain hold in humans and cause widespread disease.

“An IFITM3 deficiency makes it easier for a low dose of virus to be infectious,” said Dr. Yount.