The rapid development of COVID vaccines has truly been a game-changer, saving countless lives and significantly reducing severe illness. But even with this success, the toll of the pandemic has been devastating, underscoring the urgent need to prepare for future threats.
Aside from SARS-CoV-2, which causes COVID-19, other coronaviruses like SARS and MERS have caused deadly outbreaks in the past. Plus, there are several bat coronaviruses lurking that could potentially infect humans and trigger new outbreaks.
Recently, my colleagues and I made a significant breakthrough in mice. We developed a single vaccine that can protect against a range of coronaviruses, including those not yet identified. This approach, termed “proactive vaccinology,” aims to create vaccines against potential pandemic threats before they strike.
Traditional vaccines typically target a single virus strain, making them ineffective against diverse viruses or new ones. But our research focuses on “mosaic nanoparticles,” which incorporate multiple receptor-binding domains (RBDs) from different coronaviruses. Think of it like a versatile shield against a whole family of viruses.
The key is in the protein “superglue” we use to bind these RBDs to nanoparticles, creating a vaccine that trains the immune system to recognize common elements across different coronaviruses. This not only shields against known viruses but also guards against future ones.
However, our initial mosaic nanoparticle vaccine was complex, posing challenges for large-scale production. So, in collaboration with Oxford, Cambridge, and Caltech, we developed a simpler vaccine. We fused RBDs from four sarbecoviruses to create a “quartet” protein, which we then attached to a protein nanocage.
Tests on mice showed promising results, with antibodies neutralizing various sarbecoviruses, even those not directly targeted by the vaccine. Plus, the streamlined production process didn’t compromise efficacy—it actually exceeded expectations in many cases.
There were concerns that existing immunity from SARS-CoV-2 infection or vaccination might limit protection against other coronaviruses. But our vaccine proved effective even in mice previously exposed to SARS-CoV-2.
Our next step? Human trials. And we’re not stopping there; we’re exploring how this technology can combat other potential pandemic viruses.
In essence, we’re inching closer to a future where we have a library of vaccines ready to thwart emerging viral threats before they become global crises.
