Traditional vaccines, such as the one for chickenpox, target only a single pathogen. However, in the aftermath of the COVID-19 pandemic, researchers worldwide are aiming to revolutionize this approach. Their focus is on developing “universal vaccines” capable of protecting against entire viral families and emerging variants.
Challenging Conventional Immunization
“Our pipeline is challenging that approach,” says Alba Grifoni, Ph.D., Research Assistant Professor at the La Jolla Institute for Immunology (LJI). In a study published in Cell, Grifoni and her colleagues detail a research framework designed to create universal vaccines. These vaccines could potentially neutralize not only new SARS-CoV-2 variants but also other viruses with pandemic potential.
Understanding the Science Behind Universal Vaccines
Many viruses, including coronaviruses, belong to large families with shared characteristics. SARS-CoV-2, the cause of COVID-19, is closely related to common cold coronaviruses, MERS-CoV, and SARS-CoV. These viruses share certain “conserved” protein sequences that remain stable despite viral evolution. Importantly, these conserved regions are recognized by specific T cells—white blood cells that detect and destroy virus-infected cells.
In previous studies, LJI researchers found that cross-reactive T cells can identify these conserved epitopes, enabling them to target multiple coronaviruses. Grifoni’s lab is mapping these epitope regions to guide the development of vaccines that stimulate durable T cell immunity, even against future variants.
“It is important to induce a neutralizing antibody response,” Grifoni explains. “But we’ve shown that T cells are much more stable in the context of viral variants because they look at all the proteins of the virus.”
Harnessing Data Science for Vaccine Design
While some conserved T cell epitopes on the coronavirus spike protein are already known, researchers suspected more were hidden in global datasets. To uncover them, Grifoni’s team mined the Immune Epitope Database (IEDB), a public resource led by LJI scientists, analyzing over 200 coronavirus epitopes identified worldwide.
In collaboration with virologists at the J. Craig Venter Institute, they used bioinformatics and artificial intelligence to detect similarities between epitopes across coronavirus species. They then compared how T cells recognized these epitopes, both within and outside the spike protein. This mapping offers a blueprint for designing vaccines that trigger strong, cross-reactive T cell responses.
A Step Toward Pandemic Preparedness
As reported by medicalxpress, Grifoni emphasizes that while universal vaccines might not prevent all infections, they could reduce severe illness and hospitalizations during future outbreaks. Moreover, the research pipeline can be adapted to study other dangerous viral families, including paramyxoviruses (measles, Nipah), enteroviruses (A71, D68), and hemorrhagic fever viruses (Lassa, Junin).
“Our laboratory is collaborating with groups studying many different viral families,” says Grifoni. “We need to fill the knowledge gaps to be better prepared for future pandemics.”