US researchers cure rotavirus infection with bacterial protein

U.S. researchers said Thursday they have developed a novel method involving a bacterial protein called flagellin to prevent and cure rotavirus infection, which is among the most common causes of severe diarrhea.
The method, described in the U.S. journal Science, stopped rotavirus by rapidly inducing an immune response that would normally be activated by select bacteria.
The research was led by Andrew Gewirtz and Benyue Zhang of the Institute for Biomedical Sciences at Georgia State University.
Rotavirus is most problematic in infants and young children, who can become severely dehydrated and require hospitalization.
Rotavirus causes about 500,000 deaths annually worldwide in children younger than five years of age, according to the U.S. Centers for Disease Control and Prevention.
In the new research, the researchers studied the effects of flagellin, the main component of flagella, or the hair-like appendages that allow bacteria to move around and sense their environment, on rotavirus-infected mice.
They found flagellin triggered the innate immune system, which provides an immediate response to pathogens, to produce two proteins known as interleukin-22 and interleukin-18.
Interleukin-22 prevented the virus from entering cells while interleukin-18 eliminated the virus from cells that are already infected.
Consequently, the antiviral effect of the bacterial protein was fully recapitulated by use of the interleukin proteins.
"We've described a completely novel way to combat a viral infection by use of a bacterial-derived activator of the immune system," Gewirtz said. "It's analogous to equipping an NFL defense with baseball bats. Blatant violation of all the rules but yet, at least in this case, very effective."
The researchers expected the new method might be effective against a range of chronic viral infections of the digestive system such as norovirus and hepatitis C virus.
The team is now planning studies in humans to test this hypothesis.