Duke University researchers have successfully developed a pan-coronavirus vaccine that protects against three deadly strains of the virus and demonstrated its effectiveness in a mouse study. The development paves the way for potential human trials and marks significant progress in developing a universal coronavirus vaccine, addressing a critical global health need.
A vaccine against three deadly coronaviruses has proven effective in preliminary trials in mice, underscoring the potential of a universal coronavirus vaccine. The study, conducted by experts at Duke University's Human Vaccine Institute, was recently published in the journal Cell Reports. The innovative nanoparticle vaccine builds on a previous vaccine that protected mice and primates against infection by various strains of SARS-CoV-2, the virus responsible for COVID-19.
In the study, the vaccine protected mice against SARS-CoV-1, another SARS coronavirus that can infect humans, and MERS coronavirus, which has caused regular deadly outbreaks around the world.
"We have made important progress toward developing broadly protective vaccines against coronaviruses," said senior author Dr. Kevin O. Saunders, associate director of Duke University's Human Vaccine Institute. "These pathogens cause or have the potential to cause significant human infection and loss of life, and a vaccine that provides protection could slow or even prevent another pandemic."
Sanders and colleagues created the trivalent vaccine using a nanoparticle loaded with a key fragment from each coronavirus called the receptor-binding domain. This segment is a docking site on the virus that allows the virus to penetrate human cells, and it provides immune cells with enough information to mount an effective response to the actual coronavirus entering the body.
In earlier studies in mice and primates, researchers demonstrated that early iterations of nanoparticle vaccines were effective against multiple SARS-CoV-2 variants. Human trials of vaccines carrying immunogens from different SARS-CoV-2 variants are planned next year, including those that have been dominant since the initial outbreak in late 2019.
The current work expanded the vaccine's ingredients to include a virus related to SARS and the MERS virus. In laboratory studies and experiments on mice, researchers found that the vaccine candidate produced inhibitory immune molecules called antibodies against all three types of disease-causing human coronaviruses.
Importantly, the vaccinated mice did not become ill when challenged with a SARS-like virus or a MERS-like virus.
"This study is proof of concept that a single vaccine that protects against both MERS and SARS viruses is an achievable goal," Sanders said. "Given that one MERS virus and two SARS viruses have infected humans in the past two decades, developing a universal coronavirus vaccine is a global health priority."