Research News

A Cleveland Clinic research team has published a new mRNA vaccine candidate against the tick-borne severe fever with thrombocytopenia virus (SFTSV), also known as Dabie bandavirus. This is the second vaccine candidate a team led by Jae Jung, PhD, director of Infection Biology, has put forward in three months. There is currently no treatment, cure or vaccine for the virus, which emerged in 2009. 

The Jung Lab previously developed a nanoparticle vaccine candidate that has fewer side effects and is ideal for older, at-risk individuals. This new mRNA vaccine candidate, published in the Journal of Medical Virology, offers a second, more convenient option over multiple-dose vaccines.

"Medicine rarely effects everyone the same way," says co-first author Leo Kim, a graduate student in the Jung Lab who led the development of both vaccines with co-first author Jonathan Lai, PhD. "We made a vaccine that was perfect for one group and good enough for everyone else. But we don't want to settle for good enough. We want to make sure everyone has an option that works for them." 

Kim says a trade-off in making the first nanoparticle vaccine candidate safer for older patients is that it requires multiple doses to provide a high level of protection. The problem, he says, is that most individuals fail to complete multiple-dose vaccines. 

"We need three shots before we're fully protected against viruses like HPV, but less than a third of the people who get their first dose complete the series. Without all the doses, the vaccine doesn't work as intended," he says. "We want our own vaccines to work as intended, meaning we need to make sure that people have an option to get fewer shots." 

Dr. Lai, who works as a postdoctoral fellow in the Jung Lab, added that providing different options can potentially reduce vaccine side effects or severe immune responses. 

Kim and Dr. Lai also worked closely with Younho Choi, PhD, assistant staff at the Florida Research and Innovation Center. Dr. Choi first worked on the project as a postdoctoral fellow in the Jung Lab. He continued to collaborate on the project even after he started a lab of his own. 

SFTSV spreads through the Asian Longhorn Tick, which is already present in 20 U.S. states, including Ohio, where it has reportedly caused large infestations. Experts believe it is only a matter of time until one of these ticks causes an SFTSV outbreak in America, and the Ohio Department of Agriculture encourages people to immediately report any tick sightings and submit (safely acquired) specimens for testing. 

"I think a lot of people on our team are so passionate about this project because we've seen how this virus can affect people firsthand," says Kim, who dedicated himself to finding a vaccine after completing his military service in South Korea. "Developing vaccines is a way I can continue to protect vulnerable people against threats. Maybe if we're fast enough, we can even protect people here in the U.S. from having to experience the virus, as well." 

Dr. Jung serves as director for the Sheikha Fatima bint Mubarak Global Center for Pathogen & Human Health Research. The center's research focus includes vaccine development and population studies.

"I am immensely proud of my team. Their accomplishments truly embody the values of the Pathogen Center as they develop treatments with patients globally in mind," he says. 

Dr. Jung and his team have partnered with Cleveland Clinic Innovations to continue optimizing their vaccine candidates and preparing for clinical trials.