Universal vaccine protects mice against five coronaviruses, neutralizes variants

Several SARS-CoV-2 vaccines have moved from development to distribution in many parts of the world in record time. In fact, in New York, more than 50% of the adult population has been vaccinated.

But the emergence of SARS (in 2003) and SARS-CoV-2 highlights the need to develop universal vaccination strategies against the broadest Sarbecovirus sub-genre. Today, scientists at the Gillings School of Global Public Health at the University of North Carolina (UNC) are working on the development of a universal vaccine that protects mice not only against SARS-CoV-2, including emerging variants, but also against other coronaviruses.

This research is published in Science, in the newspaper, “Chimeric spiked mRNA vaccines protect against Sarbecovirus challenge in mice.“

To prevent a future coronavirus pandemic, researchers at UNC-Chapel Hill have designed a vaccine to provide protection against the current SARS-CoV-2 coronavirus and a group of coronaviruses known to pass from animals to humans. Using an mRNA-based approach to create chimeric spike designs – combining regions of spike proteins from different coronaviruses – the team led by David Martinez, PhD, postdoctoral researcher at UNC’s Baric Lab, demonstrates a protection against the challenge of five heterologous coronaviruses (SARS-CoV, SARS-CoV-2, SARS-CoV-2 B.1.351, bat CoV (Bt-CoV) RsSHC014 and one Bt-CoV WIV-1) in vulnerable aged mice .

Chimeric spiked mRNAs induced high levels of neutralizing antibodies largely protective against high-risk Sarbecoviruses. This result contrasts with vaccination using SARS-CoV-2 mRNA alone, which showed a marked reduction in neutralizing titers against heterologous Sarbecoviruses. Additionally, a challenge with SARS-CoV and WIV-1 in mice that had been vaccinated with SARS-CoV-2 mRNA alone resulted in groundbreaking infections.

However, the chimeric spiked mRNA vaccines used in this new study “effectively neutralized D614G, mink group five, and the UK B.1.1.7 and South African B.1.351 variants of concern.”

The authors write that multiplexed chimeric tips may prevent SARS-like zoonotic coronavirus infections with pandemic potential. “Our results are promising for the future because they suggest that we can design more universal pan-coronavirus vaccines to proactively protect against viruses that we know are at risk of appearing in humans,” said Martinez. “With this strategy, maybe we can prevent a SARS-CoV-3.”