A vaccine for the common and sometimes deadly RSV (respiratory syncytial virus) has been elusive, but scientists say a new discovery puts them much closer to success.

A new study from The Ohio State University provides a potential blueprint for finding the immunological sweet spot – a vaccine weak enough that it doesn’t make people sick but strong enough that it prompts an ample immune response, ensuring that the body will recognize RSV as an intruder in the future, and quickly mount a protective defense.

In a study published today (Oct. 9, 2019) in the journal Nature Communications, researchers report success in knocking out an epigenetic modification known as N6-methyladenosine in RSV RNA – a technique that proved to tamp down the virus and prompt a robust immune response in cotton rats.

“We now have a novel target to go after, and are working with industry toward a vaccine,” said the study’s senior author, Jianrong Li, an Ohio State professor of virology in the Department of Veterinary Biosciences.

Using a technique called reverse genetics, Ohio State researchers generated RSV that is defective in N6-methyladenosine methylation – one of the most common modifications that our cells make to RNA.

“What makes this especially exciting is that using this modified virus in a vaccine is likely to enhance a person’s innate immune response, a challenge that has stood in the way of vaccine development in the past,” said Miaoge Xue, the study’s lead author and a graduate student in Li’s laboratory.

“This approach may also work for similar viruses, such human metapneumovirus and human parainfluenza virus 3,” said Xue, who recently presented these findings at the annual meeting of the American Society for Virology.

This discovery could also make vaccine production more economically feasible because it does not slow RSV growth in the lab – a critical step in vaccine production, said Li, who is also a member of Ohio State’s Infectious Disease Institute.